Steering Box Input Shaft Seal
 

My power steering box is leaking at the rag joint. How hard is it to replace the input shaft seal?

Not to bad but been awhile since I did one. Just be careful putting the new seal in so as not to cut the seals edges on the splines. Make sure there are no burrs anywhere(learned this the hard way). Use some grease when installing. Looking at what you have done to the rest of the truck,you should have no trouble.