i am puting back together the interrior to my 74 , when i purchased the car some of the interrior trim was missing to include both quarter panel trim pieces. the car has a/c and also an option of rear window defogger in which there is an outlet on the driver side to blow on the rear window but having looked and asked a few questions no one has been able to answer is there a special trim piece with a hole cut out and perhaps a grill to cover the hole for the outlet.  the new one i got does not does not reflect any hint of if i could cut out the new one. anyone able to give me an answer................thx mfrohm74

There is a grill on the quarter trim. The factory trim panels had scribe lines on the back of them, and if the car had the rear de-fog, the hole would have been cut out, and the grill installed.
I can e-mail you a copy of the Assembly manual page, if ya want.
Do you have all of the de-fog stuff(fan motor, ducting, etc) with the car?

thx for the info i have a assembly manuel as well so that was a help, all parts are there and work but there where no rear qtr trim panels for me to go off of , i ordered new ones from corvette america and need to contact them as there are no scribe lines of the new one. also need to find a grill. thx for the help. did my picture come up on the posting i tried to get it to attach and don't know if it worked . again thx mark frohm

No pic here...
Perhaps someone here with a '74 and the C50 rear defog could take a few measurements for ya... My car doesn't have the rear defog, but I might be able to take the panel off and check the scribe lines...my trim panels are factory.