I have been fighting a power steering problem with my 6T4 Polara I had both the pump and box rebuilt by a reputable shop in nearby London, Ontario. I have had the power steering working, but lately, not so much. So, today I took the return and high pressure lines off the box, and stuck them in a plastic jug with a quart of power steering fluid in it. I had my wife spin the motor over, with the coil wire disconnected. After several sessions of this, nothing came out. The pump resevoir was full, and it did not even pump any of this out. So, I guess the pump comes off. The PITA part is that my Vintage Air compressor mounts to the power steering bracket, so it has to come off, too. I hate undoing things I have already done. I just got done replacing a new master cylinder that would not pump juice to the rear brakes. The new replacement works just as it should. It used to be, if you bought a new part, it worked. If you got something rebuilt, it worked. Not any more.