After reading this post i set out to do this swap on my 1990. I bought the reman pump from autozone pn 7145 with the tank. I found that the pumps are the same with the following exceptions: the mounting holes on the Grand's pump are smooth not threaded, the high pressure fitting is different but swapable from the old pump and the hole that the tank mounts is not the same between the pumps. You must use the GC tank. This swap can be done by swapping your high pressure fitting from the old pump to the Grand pump. You will have to find and use mouting bolts that run all the way through the front mounting bracket, through the pump and out the back of the mounting bracket. Also you will have to use the Grand's pulley because it has holes to run the mounting bolts through. If you use the old pulley you will have to pull the pulley every time you want to remove and install the pump. You will also have to use different high pressure hose do to the tank differences and don't forget to plug the second return to the tank. Hope this helps someone..... blaise
1990 pump
2001 Grand Cherokee v-8 pump
1990 High pressure fitting
1990 pump mounting hole
2001 GC mounting hole
1990 pulley
2001 GC pulley