They designed a rear suspension system that stays beneath the bed floor, and still gives 18-inches of wheel travel. They did it using a cantilever system much like the F1 guys did.

Rear suspension: Spring-under using Deaver F67 leaf packs, Total Chaos spring plates, spring hangers, and shackles. Drew designed and built the cantilever system.

Here we explain mounting a cantilever airbag. Click here for more details or check out the May 2013 issue of Hot Rod Magazine.