Hey Flighter.
My 5cents.
Mine is a treet car so i saw no point in going nuts bare metalling the underneath and inside (it does look nice though)
If i had the cheque book i would do it.
I too knew the history of mine and it was in very good condition. This being said I don't like easy way outs and dodgy short cuts. If i'm gonna spend 2 years and $1500 on paint - i want it proper as i can do.
So - i got a car polisher (like a 200mm grinder but slow) and went to tool place in welshpool an got 200mm pads like these
www.eastwood.com/media/catalog/product/cache/1/image/49827f4e4ab68e0bf91ffd22f523ef02/p1626.jpg You can also get little 100mm ones for the baby grinder for tighter spots.
They get down to the metal real quick without cutting into the metal. You'll go through a few.
I do not like paint stripper and putting water near my bare metal. Just don't liiike it.
I got the engine bay sand blasted - well worth it.
Then i bought a little sand blaster nozzle from supercrap and some garnet powder and blasted every thing i could get my hands on. Was great for around doors and anywhere i couldn't get the grinder to.
Window surounds ets.
The inside i left alone - as you said - carpet and trim and you'll see none of it. As long as there is not rust.
The underneat had been deadened from factory so no issues for me but i pulled everything out up on stands, donned the mask and coated it in fresh deadener. So all sealed and street pretty.
Time consuming but didn't cost a bomb.