THere were a couple old drag racers that used to narrow housings. They were crude but they worked without issues. They always said that if the axles slid in easily it was close enough. A torch, a grinder, a stick welder and 3 jack stands. Right or wrong, that's how they did them.
I've seen you tube vids of a guy shortening the long axle side of an explorer 8.8 with a couple pieces of angle iron and a couple c-clamps. It actually wasnt as ugly as you might think.
Bottom line, if it works, it works. If it's not jigged straight, the axles won't go in, well.......then complain.