I know I've seen kits to use GM Pumps on Rustang 2 racks that drop down the pressure. Pressure Kit
I believe you can also open up the pump and cut the spring instead. You may also have to add an adapter to drop down the flow rate. Flow reducer

The Spring or Kit mod, drops down the pressure but does not slow down the flow (GPM) rate that might also be effecting the steering. I've heard of guys using either of these solutions or both to get a better feel, that's the extent of my knowledge on it though hopefully that will get you in the right direction until someone more knowledgeable can jump in and correct me or fill in more info. Another option might be to give the guys at Borgeson a call or email, I bet they'll know just what you need to do (Ie.. what they can sell you). If you go that route be sure to check back in and let us know the solution.
Steve
"Mongo"


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