New '72 Jimmy on the site - A few restoration questions

[Jordo33]

Hey guys (and gals),

I just found a '72 Jimmy and brough it home... so now the work begins. It's all original and survived the 900 mile drive home - they don't make them like they used to. It's all original, and most everything is there, it just hasn't had much done to it in the last 40 years and needs a bunch of work to make it pretty again. I originally wanted to drop the body on a newer frame with a diesel, but I have the protect o plate to prove the engine is original to the truck and it'd be a shame to separate it. 350, manual tranny, 4wd

So question time:
-It obviously runs, but the exhaust is patched together right now. Does anyone know if there's exhaust kits out there, or is it worth just going to a good shop and having it custom made? Also, thoughts on getting some aftermarket headers (looking at earlier threads hooker competitions were the best) vs. staying original?

-How hard would it be to put A/C in it? Some of the lines are in it, but it sounds like those were run no matter what and just used if it had the option. I know I'd need to get the condensor, brackets, heater box...

-There's some minor rust at the back of the bed, but the rest of it's in good shape. Any if there's patch pannels for that? (I haven't found any yet)

-The only body pannel in rough shape is the tailgate - any idea if regular pickup tailgates would fit as well?

Thanks!