C6 Corvette F55 Console Installation
(updated 10/6/07)
Used with Permission from Ray Kawal
This modification allows the installation of a 2008 console into a 2005-2007 C6 Corvette with F55 Suspension
Without the F55 suspension option, the 2008 console is a direct replacement for the 2007 and earlier console. But for 2008, the F55 Suspension option changed with a new switch and a new way of mounting the switch. The older switches were mounted in a removable plate, sometimes called the "tombstone" plate because of its shape. The same console was used in all Corvettes, and a blank tombstone was used without the F55 option. The 2008 switch mounts directly into a new console made especially for the F55 option.
The console on the left is the earlier 2005-07 console for all models. The console on the right is the new 2008 console for the F55 suspension option.
If it weren't for the switch, the new '08 console would fit perfectly into an old C6 Vette.
Now let's look at the switch differences. The one on the left is the old 2005-07 switch. The new 2008 switch is on the right.
The protrusions at the bottom are the housings for the switch electrical connectors.
The new switch snaps into place in the square holder seen in the top photo.
But there are a couple of problems - the first is electrical. GM redesigned the F55 circuitry, so the 2008 circuit is different from the early circuit.
Here is the earlier circuit:

The old switch used a 4 pin connector with Pin 4 not used
Here is the new circuit:

The new switch has 12 pins, but 7 of them are not used.
But this new switch can easily be used for the earlier circuits if an adapter cable is used to alter the switch functions.
Note that in the early F55 circuit, all the switch does is provide a ground to the computer module when the Sport Mode is selected - it couldn't be more simple.
So if the new switch can be used similarly, the electrical problem is solved. We just use Pin 12 for a ground connection and connect Pin 10 to the computer (Sport Mode) wire.
Note that the lighting circuits are basically the same - a wire from the dimming cluster and a ground wire.
So electrically, we use Pin 6 and Pin 12 on the new switch for ground, and connect both pins to Pin 3 of the earlier 4 pin connector. We connect Pin 5 of the new switch for the lamps to Pin 1 of the earlier 4 pin connector. And finally, we connect Pin 10 of the new switch for the computer signal to Pin 2 of the earlier 4 pin connector.
Here's a view of the 2005-2007 4 pin connector:

And another view:

The black wire is ground, the tan/white wire is to the computer, and the gray/black wire is for the lamps.
Looking into the connector:

The four rectangular holes on the right are what we want to connect into
Now let's look at the new switch:

If you look at the pin diagram new F55 circuit, you will see that the four pins we need to connect to are on the left of this photo.
We need Pins 5, 6, 10, and 12.
The six pins on the right are of no use to us.
Also note that Pins 6 and 12 are next to each other - our ground pins.
Pins 5 and 11 are next to each other, but Pin 11 is not connected to anything.
Pins 4 and 10 are next to each other, but Pin 4 is not connected to anything.
So we need an adapter cable that will connect the 2005-07 4 pin connector to the six pins on the left of the switch.
OK, we've solved the electrical problem. Now here's the next problem.
If you look into a 2005-2007 console with the old switch removed, this is what you see:

See the big rectangular cutout next to the bolt? This is to provide clearance for the 4 pin connector when it is connected to the old switch. The plastic connector housing on the old switch fits into this area when it is installed.
But look at how the new switch is installed in the new console:

and compare it to the old switch below.
Look how the old switch connector is on the right of the tombstone plate (looking from below), which fits into the rectangular cutout of the first photo.
But the new switch connector is at an angle and left of center. What happens is that the new switch plastic connector housing interferes with the area around the bolt in the first photo - it doesn't fit into the rectangular cutout. If you try to install the new console with the new switch, you will find the switch hits the area near the bolt and the console will not go all the way into its proper place.
So here's what we do. We can't use a 2008 connector anyway, since the circuitry is different than the earlier versions.
So we simply cut off part of the plastic connector housing on the new switch:

Use a hacksaw or even a pair of diagonal pliers and cut off the plastic housing so it is about 5/16" - 3/8" long, just clearing the pins.
Once done, the switch will not interfere with the area below, near the bolt.
Another shot of the modified switch:

Now we can make an adapter harness to fit both the 4 pin OEM plug and the new switch.
This adapter harness must connect to the switch pins noted above, but it must not protrude much below the bottom of the switch to avoid the interference we just cured by cutting off the plastic housing.
Here is the prototype we just installed on Mike Morehouse's '06 Vette:

Note this connector will fit 6 pins.

Another view:

Note this portion of the harness fits over the proper six pins of the new switch and protrudes not much beyond the pins themselves. It will easily clear the area noted above around the bolt.
Here are some finished adapter harnesses:

Here is the 6 pin connector on one end:

and the 4 pin connector on the other end:

Here's how to plug in the adapter harness into the modified switch:

It's easier to install the switch with the adapter harness into the console before installing the console.
Be sure it is plugged into the correct six pins as shown in the preceding photos.
Here is how the adapter harness is plugged into the OEM 4 pin connector:

The white plastic tab prevents the plug from being inserted incorrectly.
Obviously, on the 6 pin end, care must be taken to push the connector onto the proper six switch pins!
If you are interested in building your own adapter cables, here are some suggested parts you might want to use:

To make the 6 pin connectors, I pulled the pair of pins on every 4th row and cut the long connector block with a hacksaw. I had some 4 pin connectors with the white tab, so I used them to have a way to prevent incorrect insertion into the OEM 4 pin connector. You could also use the multiple header on the left and just cut off 3 or 4 pins to suit your needs. Other than the above parts all you need is some 22 gauge wire, solder, and some heat shrink tubing. I used a heat glue gun to seal the 6 pin connector after it was soldered.
Here is the wiring on the 6 pin end:

The red wire is the computer signal (Sport Mode) wire connected to Pins 4 and 10 (remember Pin 4 is not connected in the switch)
The white (middle) wire is the lighting wire connected to Pins 5 and 11 (remember Pin 11 is not connected in the switch)
The black wire is the ground wire connected to both Pins 6 and 12.
Here is the wiring on the 4 pin end:

Again, White is the lighting wire to Pin 1 of the OEM 4 pin connector.
Red is the Sport Mode wire to Pin 2.
Black is ground to Pin 3.
These aren't hard to build, but I have a few adapter harnesses available if any owners want them.
Paypal me ten bucks and your address and I'll mail one to you.
Here are some procedures and tips for removing and installing the new console: