My '77 F150 is indeed a high pinion setup, and the F250 axle, since it is out of a '78 is also a high pinion, so it is a direct swap. As 75f350 mentioned, the 77.5 and earlier F250s (high-boy) are low pinion setups.

75F350, thanks for the clarification on the wedges, that is good to know, and all the more reason to keep the stock housing and swap the gears. I really think that this will be the easiest way to accomplish my goal. Thanks for the help on the steering as well, this thing really handles horrible right now with the stock steering and oversize tires; the geometry really needs corrected. I think the later 1/2 ton setup is the easiest way to do this.

While we are on the subject, where can I find a new lower spring cup (mounts on the radius arm)?