PPG Durethane fits that, I think it was a 2:1 mix ( plus reducer) and you could polish it on the day after you sprayed, but not on the third day,, it was brutal to polish, but man it held up to most anything, it was like a cockroach,, anything up to a nuclear blast LOL
for the record, I pretty much disregard any of the ultra hi end clears when discussing here, I dont know many who would want to spend the money, or deal with the ultra hard surface here,,,
for my money, PPG 2021 or 2042 is about as top of the line as you would want to go in our world,, ( and yeah, its not really top of th eline in the grand scheme,, I love Glasurit clears and Sikkens clear is water wet and clear awesomeness,, but it can be spendy)
higher acrylic levels make it easier for the hobbiest,
thanks for the additional info though,, always good to learn more,, I have never heard of Bostic-Finch, maybe the next show car I spray,,,,,,,,