Mark asked for any painters to chime in so here goes.
I have been painting planes and cars for many years now and have a little experience. Most automotive paint systems are now acrylic urethane,
urethane or a polyurethane that are very good UV protectant paints. I recommend staying away from your lacquers and synthetics. Yes, many
lacquer primers are cheap but do not do anywhere near the job of a good 2K (means 2 part) primer. Most of these 2K primers are heavy build
(good for final sanding before sealer) and hold very well. They are also UV protective. Price for a gallon kit (one-gallon primer -
one-quart activator) is normally about 65.00. One gallon should do most of the KR if your bodywork is smooth.
I use a filler called Basecoat made by USC for my "bondo" heavy filler and then finish with a filler called "Icing" also by USC. These sand
very easily and hold up well. On large surfaces you can use a polyester spray (take a gun with a 2.0 tip or larger) and sand down. A
polyester spray is also known as "sprayable bondo.” It costs about 35.00 for a quart. I normally use this on large flat surfaces that have
to be very smooth. It sands easily (using 18" block.)
After this stage you can go directly to a 2K primer, sand and then I usually mix 1/2 2Kprimer and 1/2 paint color to make a tinted sealer that
is wet sandable before shooting topcoat. As far as top coats, any good acrylic Urethane should hold up well, or an acrylic enamel with a couple
coats of urethane clear on top. Urethane clears are great - 75.00 a gallon or so - easy to color sand and buff. I use Nason/ Transstar/ Dupont/
Imron and all seem to do well. The biggest problem I have had is with Imron's Urethane paints. They are expensive and near impossible to make
any repairs to without reshooting an entire section. They don’t color sand and buff well at all. For ease of maintenance use Nason, Transstar,
and others that are acrylic urethane.
I have an 18’ X 25’ downdraft paint booth with 10-foot ceilings that I use for my car restorations. I told Art Bruce, that since he is a local
guy once he gets to the finishing stage, I can make my shop available for him - or others if interested - to come finish wings / fuse and paint
them here. I can also make my services available if you want me to do it as part of my business. Just a suggestion. I know it is hard to find
a paint booth to do this work at some times - most shops are not interested in helping broke KR builders paint.
I hope this helps - any more questions - just ask. I don’t claim to know it all. The paint business is like computers - it changes very quickly
and is hard to keep up at times. That is why I enjoy antiques I guess.
Happy Building - Bill