The fourth line of the second verse of Steve Earle's Copperhead Road goes 'Just shot a coat of primer and he looked inside' as far as I can discover. Maybe I'm being dense but I can't make out what this means. The context is as follows:

'Now Daddy ran whisky in a big black Dodge
Bought it at an auction at the Masons Lodge
Johnson County sheriff painted on the side
Just shot a coat of primer then he looked inside.'

The only sense I can make of this is that it should be 'short a coat of primer' i.e. to paint over the sherriff's logo but none of the versions I can find say this. Anyone got an explanation?