Hi While I am not a Firebird expert , I have my first one here for a total rebuild , I have been restoring cars for almost 40 years .
Rubber stuff , oil breaks down rubber over time , so , if it is looking worn or brittle I would replace what I could . It's so much easier with th engine bay empty .
Cleaning , I like simple green or purple power . I have a steam Jenny so that makes things easier but you can clean it with a garden hose and a semi soft brush .
Eastwood sells engine paint , or you can use spray bombs if you don't have spray equipment . POR 15 is more for floors and that sort of thing you have to see how much rust you uncover in the cleaning process .
I have seen a lot of firebirds with a semi gloss engine bay and fire wall , so I am guessing that that's the way they came . Some one else can answer that better , while you're in there look for things like steering issues and the firewall seals , much easier to do with the motor out .
