Auto body repair & detailing: Front end conversion, adhesion promoter, grill shell

Question
I just got a front end conversion kit for my 91 Chevy pickup, it converts it to a 99-00 Cadillac Escalade front end.  It came with new front fenders, hood, grill, bumper, etc...  All the metal parts are in the black primer and I'm not sure if I need to do anything to the inside of the fenders before installing them to prevent rust later or can they stay like they are.  Also, the grill shell and bumper are black plastic (ABS?) how does that get painted so it won't crack with the parts flex?

Answer
Hi Matt,

The primer that is on the parts is E-Coat. For maximum durability you need to scuff sand and prime them using a Epoxy or Urethane primer sealer. This will help keep the panel from rusting out from the back side.

For the flexible stuff: If you use a good quality basecoat/clear coat system you won't have to worry about the flexing parts cracking the paint. I would use a epoxy primer sealer such as DP50LF with DP401LF Hardener. DP 401LF Hardener is designed for use on flexible parts. Before using the Epoxy use a plastic adhesion promoter such as Bulldog Adhesion Promoter. You can find it at this link: http://www.repaintsupply.com/pd_kleanstrip.cfm This should give you great adhesion and flexibility. If you have any other questions please feel free to ask.

Gary