whats a good wrinkle paint to use?
woah... For what? You cannot just pain crinkle paint over existing crinkle paint. The prep work for this is actually harder than with regular paint and it is much more persnickety regarding temp and such.
I'd clean it with a damp (not wet) soft scrubbie and dawn dish soap.
Direct answer to the question posed: Plasti-Kote or VHT are the brands that I have had the best results with.