Wheel spin

If I was trying to hook this car up, I'd move the battery to the trunk first then do what ever your going to do withthe rear springs.
I'd make sure the pinion angle is correct, add a pinion snubber set correctly meaning down for autocross, up for drag, then play with the rear shock adjustment.

I'd move the battery to the trunk no matter what. That mod is just a win win all the way around.

Just keep in mind the snubber won't help you on the street but it can be a useful tool.