you need to convert to a IFS power steering box and yes, convert to a power steering setup if yours is not equipped....
the 91 stuff is different from your truck..... the pre85 brackets and pump were different than the 85 and later..... they do not bolt up to each other... their holes are just slightly off. you cant put a 84 pump in an 85 bracket... however if you have the pump and brackets from the same model year, their shouldnt be a problem with bolting it to the older block
i recently put an ifs pump on my sa truck, not because i didnt have a pump, but because i had no brackets, i got brackets from an ifs truck, and my pump wouldnt fit, so instead of getting other brackets, i used the pump that fit the brackets....
