It looks like someone took a 318 Satellite and built themselves a nice little Mopar street machine with a 440. You're not going to lose anything by leaving it like it sits; in fact, the previous owner didn't go jacking around with an original Road Runner or GTX and instead, did up what looks like a straight little Satellite. The first two letters of the VIN tell you what you have: RP=Satellite; RS=GTX; RM=Road Runner, RH=Belvedere II; RL=Belvedere I.

I park my son's Chevy truck next to my Mopars, too.

Pessimist - Sees glass as half-empty. Optimist - Sees glass as half-full. Gov't- Sees glass and takes it from you because you have a glass.
Political Correctness: A philosophical belief system bereft of common sense and logic, that supports and rewards ignorance and stupidity.