Djam, the basic type of brace that you are describing has been used alot over the years, but isnt much chop on anything serious off road. Dirt racers etc yes. Bush65 has pointed out that a truss on top can be as functional as a truss on bottom. I have seen some very elabirate trusses with the middle section unboltable, but these things weigh alot and are needed on hardcore 4wd racers.

