Sounds like fun. A lot of work to make it trustworthy. Don't go thick oil, go thinner and synthetic, the oil passages need to be cleaned and synthetic will do that. Yes, the PCV on the N/A engine has a flame trap near the throttle body and it does get dirty.

Next time you start the engine, let the engine warm up to 'normal' on the gauge. Then 'ease' on the throttle. I guess there is a lot of dirt in the throttle body and probably a few cracked vacuum hoses. Bring a scan tool with you, this is an OBDII system with a port by the ashtray.

The tires will have flat spots, so don't go 70mph anytime soon. The cabin air filter, if it has one, will help eliminate the musty smell. Look for mouse nests!

My estimate for roadworthyness is about $1,000. Don't fret about any EVAP codes, you will get some. The gasoline may be 'old', but don't drain it, just fill the tank with regular.

--
Keeping it running is better than buying new