The earlier fuel rail will bolt right up. If you were to swap to the later fuel rail you'll also need to change the fuel pump and the fuel tank (the regulator was moved to the fuel pump assembly in 96, the later fuel rails have no return lines). The later fuel pump assembly mounts into the tank differently than the earlier tanks as well.
Only thing that needs changing on the later manifold is the PS brackets as you mentioned already.
My 88 MJ has the stock 88 block, 92 head, 00 intake, 94 fuel rail, 92 throttle body, 96 PS pump/brackets, and 00 valve cover.



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