Powder coating is faaarrr from 'overrated' if it was then it wouldn't be around still. Iv painted cars myself ( not my car, yet ) a corvette to b precise. And if this guy wanted to PC his corvette then I think it's good enuff for a panel van ;). It can go onto bare metal but I would 100% powder prime the hell out of it. If ur powder coat if flaking off, it wasn't cured
properly I AM going to powder coat My van. Cost is no problem coz I'm the coater doing it! Beautiful colours available on eBay or can get a traditional sandman colour made to suit!

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P.s Rico I've painted heaps of bullbars! We do Aussie 4wd's bullys!
If anyone in Adelaide needs some powder coating done PM me!