on my 1991 L98 Auto Coupe, have the console, upper dash trim, and right and left lower trim and knee panels all off, but still can't see how to get these out.

It looks like (maybe?) the instrument panel bezel and cluster need to be removed? The center plastic "frame" over the metal CCM/DERM supports won't come out...

Thanks all!

I took the DERM out not too long ago. You'll have to remove the Radio to unplug the wiring. Access you'll get only from the drivers side behind the carpet. There is some kind of carpet-flap that is attached with a couple of screws.
Remove the bracket behind the carpet and the DERM pulls out to the side. The CCM is right behind it and is held by the same bracket.

Are you having a problem with the CCM? You do know the car won't run without it.

I just did one(CCM) on a '95...what a friggin pita!! If you replace the CCM, you'll also need to have it reprogrammed, or the car won't start. Supposedly, it may start and run for about 50 miles or so, but after that, it can't be programed...so the manuals say.
I had to replace this one because the dash display was dead, and the car wouldn't crank with the key. I could jump the anti-theft start relay under the dash, and it would run for about 5 seconds before the injectors got shut down by the anti-theft...

I need to take out the derm and ccm because it looks to me like there might some some wiring damage or possibly damage from an old electrical fire in there and I want to check it all out.

I don't envy you that fix, dude... I really don't.

I hope you have the Helm Factory Service Manual. Without, you will be flying blind. Check ebay or www.helminc.com.

Thanks to all I got both the CCM and DERM out, the DERM and air bag sensor appear to have suffered damage from some electrical fire or short in the car which has impacted a number of wires, so I've ordered a replacement DERM already.

Can anyone recommend where to get a replacement air bag impact sensor? Thanks again to all!

I would call either Jason at www.vette2vette.com or Chris May at Superior Chevy, 1.800.728.8267. Either way, tell them I sent you. Jason runs a Corvette salvage yard and Chris is wholesale parts manager at Superior Chevy. Both have great customer service.

Casey highly recommends www.maxxwrench.com, too. I haven't dealt with maxxwrench yet, but I respect Casey's opinion on these things... tell them at Casey from Australia sent ya.

If you need any wiring harnesses, I would contact Jason at Vette2vette. No question. Used is the way to fly for that part.