On the top inside of the seal housing is a hex drive keeper threaded into to the housing. I forget what size it is, but you can use a bolt with a head the same size with some jam nuts to remove this, and then you will have to pop out the seal on the bottom. If you are real careful, it will come out without damage, but be prepared to get a new one.
I chromed my arms instead of PC them because on the bottom of the ball joint is a nylon bushing that will melt in the PC oven. But if you want to try then you will have to remove the rubber boot and clean all the grease out. Then I put some brass spacers on top of the ball joint with the castle nut on top to keep anything out of the joint. When I put mine back together I used safety wire around the boots instead of the pain-in-the-ass clip that was originally on there.
Hope this helps...