Since pulling the head is not a real big deal with these 4 bangers, you could do that and then have the valve seats cleaned and valves inspected. Checking the rings and bore at the same time. That will give you piece of mind and something to do :>)

There is a mechanic in Wis who is selling PV parts on Craigslist once in a while, I believe his name is Rob and did a lot of work on your car. Then again, I never met the man and don't know for sure. He would remember C.A.

New door seals will be a nice plus. As would insulation under the hood and inside the firewall.

I wouldn't use 40W, the RMS really only leaks from the top half due to being parked for 7 months every year. You could pull the tranny/clutch and replace the seal.

I always attributed the black tailpipe to the weber pulling too much vacuum from the PCV... Not blowby.
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My back feels better when I sit in a Volvo seat