It's pretty easy to take the steering box out of the truck. I don't think you'd be making it easier by not removing it since you'll want to clean out the inside of the box when you rebuilt it and then seal it good with permatex on the gasket and adjustment threada, and while its on the frame that'll be tough to do.
There are two bearings, one seal, one gasket, one adjustment screw, a set of ball bearings and one bushing in a steering box.
The bearings and races are on the steering shaft, one is at the end of the box and the other is at the top. You could change those without removing the box, but you'd have to pull the column so not removing the box doesn't save much effort.
The paper gasket, bushing and adjustment screw are in the side cap. You could replace both of those without removing the box. When you replace the bushing you may have to ream it out to make it fit your sector shaft, I used a brake cylinder hone on the end of a drill and it worked very nicely.
The sector shaft seal is on the side of the box where the pitman arm is. You'll have to remove the pitman arm, side cover and sector to replace that seal, so not pulling the box doesn't save you any effort to do that.
The ball bearings are in the worm gear which is on the steering shaft. You could just remove the column to replace the ball bearings, but not pulling the box doesn't save you much time on that either.
Good luck!
