A Chevy-powered Saab? Hmmm...several expressions come to mind...
One man's trash is another man's treasure.
To each his own.
He marches to the beat of a different drummer.
You can't polish a turd.
It sounds like an ugly fat chick. Fun to ride, but don't let your friends catch you! And it's like a horrifying car wreck: If you do a build thread, I will HAVE to read it.