use your google-fu:

http://www.google.com/search?q=%22shoot+a+coat+of+primer%22

The present tense is fairly common as a phrase. If you use the verbatim song line, though, you'll get a lot of lyrics pages.

I agree, a 'coat' indicates the whole car was covered, not just the logo.

Also, "big black" vs. "big block" isn't helped any by the actual video for the song, because the car shown is black.