I think I have seen the stock rollbar your talk'n about, is it the one at the rear of the truck. There is an 89 diesel jimmy at a local yard that seems to have a factory rollbar in the very back of the truck it looks kinda skinny but it is holding up another blazer on top of the jimmy so it must be strong enough. I would like to grab it to use as a rear support for a rag top if my truck is ever finished. I don't know if the stock rollbar would be worth using really there isn't much there if you are doing a whole cage.