"napa brand sray can paint is the same paint sold as they sell for painting cars so it offers the same rust and surface seal"
:rolleyes: BS.
What NAPA sells for painting cars is a well known name brand of professional multi-part automotive finishes. These consist of pigments in some type of multi-part binder system (urethane, epoxy, acrylic,...) When you combine the parts of the system prior to spraying the paint, you start a chemical reaction -- and you only have a limited "pot life" before it's too thick to spray. And it's the chemical bonds formed during this reaction that seal water out, and bond the paint to the layers underneath. It's impossible to sell this in a spray can, because the bonds would form on the shelf at Wal-Mart, and you wouldn't be able to spray it when you get home.
That having been said, I missed the word "interior" in your original post. I've done a few interior trim pieces that way. They came out looking decent, but NOT professional. Maybe some of you guys are better with a can than I am. If I went this route for the whole interior (including floor?), I'd make darn sure the cab were water-tight. But then, that's good advice no matter what paint you've used, right?
I guess the point is, it shouldn't hurt anything on the interior, as long as it's kept dry. Worst case, you sand or strip it later, if you don't like the way it looks. Have fun with it -- and I hope it turns out nice.
Cheers,
mark.
'51 3100
IRWIPI