Well it's true, I should have known this would happen. 

Started with fixin' up the seats and morphed into  a full blown project. 

Rear wiring harness shot to tailights, tailight lamp housings corroded, seat belts shot, leather seats ugly, carpet disintigrating, antenna looking bad, radio cuts in / out, body drain hoses to wheelwells falling apart, 3 doors behind the seats all cracked, side marker lights look like crap, jack compartment all rusted from leaking drain hoses...........geeez.

Once ya start ya never know how far it'll take you.  Pulled all this out over the past few weeks. Started cleaning up the pieces and ordered the parts. It'll be fun.

'Tis a labor of love to be sure...!!!

I have found that most "simple projects" turn in to something much bigger. That applies to not only cars, but house projects too!

Good luck with it!

I have been there with my '79's interior.   Shop around for parts.   My son helped and corrected the rats nest of wiring under dash and console; before replacing the carpeting did add two layer soundproofing.   I have a file folder full of receipts, and have never added up the cost.   You will learn a lot about C3's... enjoy!