I used KBS on my Diner field. It worked pretty well and was easy to apply. I chose to brush it on after thinning to about 30% or so. 2 suggestion with brushing is 1) apply a layer of spray clear first. Dragging a brush could smear your work. 2) Apply in very thin coats and once you brush it out LEAVE IT ALONE. Do not continue to brush it as it self levels nicely. I don't think you have to sand between coats of you do it in a certain time frame ( double check though)

Only use KBS thinner as it's apparently specially formulated to work with their clear. Even if it is a marketing gimmick, I wasn't about to risk 4 months of playfield restoration to save a few bucks.

I got pretty decent results but I did have some separating at ball impact points and various places around the field. Not very noticeable during play TBH. Probably because I rushed a bit putting it back together.

https://pinside.com/pinball/forum/topic/williams-diner-restoration