I worked with a guy back in the late 80's that had a 41 Ford PU that was an ISCA national winner for two or three years in a row in the mid 70's. He painted the truck with RM black lacquer. He still had the truck in the late 80's and brought it out for a show in Sioux Falls. I watched him and his wife prep it for show. They did this every time they showed it on the circuit.
Here's their recipe, Eyeball.
1-Very carefully wipe the truck down with damp very soft towels and dry with very soft towels.
2-I can't remember the brand name wax they used but it came in a tube. It was a carnuba wax with a glaze in it. They would go over the truck 4 to 6 times in a row (wax on-wax off) with very soft cloths, until the wax wouldn't buff off without smearing. Then they would let it dry and go have some lunch.
3-Repeat step 2.
4-Repeat step 2, but now they were down to 2 or 3 coats, because of the build up.
5-Using good lighting, they would look over the truck and see if any spots still showed swirl marks and put more wax on these areas.
6-When they were satisfied that it was good it was put on display and rechecked per step 5.
7-During the show, it was dusted lightly with a soft feather duster very frequently, no more polishing was allowed.
They did kind of a quick version for the Sioux Falls show and it took 4 1/2 hours. It looked like a wet lollipop! I was amazed how wet and deep the shine was.
Every 2 or 3 shows they stripped all the wax off with wax and grease remover and started the process over.
They were from Siuox City, Iowa and they showed the truck every weekend during the ISCA season. They would leave Thursday nite to get to shows as far as 1500 miles away, go thru this process, and then drive home Sunday nite after the show. In order to get enough points they had to get first place in enough shows to beat competitors who were showing nationwide coast to coast at ISCA events. They did this staying in the central US and only made a couple west coast shows. I can't imagine the stress and work.