Installing splitter
 

I just picked up a GT2 splitter from Rennspeed (http://www.rennspd.com/PImages/964-05.jpg) for my racecar and I'm wondering if anyone has mounting suggestions ...

I thought about using rivet nuts made specifically for plastic and with a matching bolt and washer - I figure one every 6-8" would be a pretty solid mounting. Any chance someone knows the thickness of your average bumper material?

Edit: seems like expansion nuts might be a slightly better option, just thinking out loud