41 and 42 are for the right side, and 91 and 92 are for the left side.
Your g/f sounds cool!
This is a huge picture, but it's one of my favorite because it looks like he just rolled forward, but notice there aren't aren't tire tracks in the dirt behind him (to the left). That's because he's actually going through the turns sideways. If it wasn't for the blur on the tires, you'd never even know the car was moving. 700 hp, N/A. You gotta love it!
Here's a link to the team website, if you're interested:
Jim Porter Racing
Take care,
~Chris
