We straighten axle housings in-house. A large press, line bar and holding fixture is what we use. They are all done cold. Here's a couple pic's of before and after. Good luck on your project!
that's how i have done it.
also use that method when narrowing the rear housing. i use two support slugs for the bar at the differential bearing locations as well, so everything is in the proper location.
doing it this way insures axles will slide in without effort.
one would be surprised just how off a factory axle housing can be at the ends, and still function just fine.......
