Power steering box - just leave it be?

[msg]

I had some 8 years ago paid a local garage to do a power steering conversion on my 66 and it was a great investment..drove so much better. As I have been tearing down the truck to restore I never really notice how horribly the caked on grime was. And since Im restoring I thought to clean it up and put some paint on it. Today I started to chisel off the crud and it got me wondering what I should be doing other than just a clean and paint. Since the gear box was removed from a 72 in a junk yard I found the 72 shop manual and it reads that it doesnt need anything unless its leaking. I am not sure if I should just leave it be, or have it serviced. If anyone has any pointers on this please let me know. Again, it worked great before it just looked terrible.