Same white primer on an AFM with a paint scraper and heat gun just prior to going at it with an orbital sander.
From memory out of the late model machines from Bally Williams, only MB and CC had actual cabinet decals due to industrial action at the time by their main cabinet supplier Lenc Smith. The first 100 or so MB have screened artwork as the strike action happened just as MB was being manufactured but the rest are decals. That's why most original MB and CC you see have wrinkling around the legs.
Plus they made separate standalone cabinet decals as well for the conversion kits for SWE1 and RFM.