I guess it's a little different here in NZ thanks to the weather.... When I was panelbeating/painting full time we had no issues with putting 2k over old lacquer paint finishes. Obviously putting 2k clear over a fresh lacquer base was always a big no-no because the evaporating thinner in the lacquer would lift the 2k clear in no time...! I guess because our temps don't get up near what yours do, then the lacquer under the 2k never mis-behaved and caused us any problems. Interesting conversation for sure. I still use lacquer as a top coat on my paint jobs, I know it's not as hard wearing as 2k etc, but I don't have access to a booth anymore and I find it really hard to see what i'm doing when applying the clear because I have no extraction system in my garage and the mist makes it too hard to see what i'm doing within a very short time...! Also, I can get a nice deep, flat, mirror finish with with my lacquer clear after many hours of wetsanding and polishing. I always prime with 2K primer and dry sand and re-prime my repairs to stop shrinkage, which works a treat every time. Lacquer primer is just awful and I will never use it again. Anyway, new to the forum and always looking to keep my hand in the panel and paint game, so i'll be following you fella's posts/tips and advice closely! Cheers!