Schematics on steering gear

1989 Crown Vic 5.0 Power steering kicking in and out. Fluid is heating up extremely fast and extremely hot. Replaced pump and checked all lines everything is ok there. I think the problem lies in the box on the end of the worm gear where the lines feed in. Problem is that the box is pressed onto the worm gear there dosent seem to be a way to access the internal mechanism. Can any help me with this or tell me where I can find CAD drawings or schematics for this part? Replacement part is $122.00 and that is for the worm gear and everything, but I dont need all of that just the box.