Inliners International Forums General Discussion Engines 50-239 and a 54-239 swappable parts?

Hey guys, I am a bit of a newbie so I have a million questions, but are things like fuel pump, manifolds, head, carb all swappable on these 2 different years? looking at them, they look pretty close, but there are some oddities.

Thanks, also, is my car 54 pontiac positive ground?

Could possibly get tech help at www.Kanter.com. They list rebuild kits,restoration parts, shop manuals, etc for cars & trucks from 1930-1986. Noticed they listed Pontiac 239. Product catagorys on left side of page. e-mail and phone#'s listed.... Are there any INLINERS out there that are knowlegable of this engine/