I have mountain bike wheel that has a deore dx hub on it.
its 7 speed hyperglide spaced to 130mm
I always worry about riding my bike with a 7 speed uniglide too much because when the cassette wears out ill have to buy used or dish out more than I have invested in the bike for a NOS cassette.
could I buy a shorter axle for the hub so it fits for 126 spaced dropouts and when it comes time to build another set of wheels use the dx hub?
to me it sounds like it will work,
but it seems like a simple solution to something I've been over thinking for awhile now.
any thoughts?
has anyone done this?

also I saw this video and was contemplating doing this aswell

https://m.youtube.com/watch?v=oaBQHCU9TDw

I think that would work, but you could also just replace the freehub body with a Hyperglide one. They're less than $20, usually.

*edit, ah, yes, that's the video you posted. It's super easy, I have done it several times.

it looked really easy. might try the conversion first. just for the experience

Did you know that Uniglide cogs can be reversed when they wear?

Loose Screws has just reopened, and have some Uniglide cogs.

Loose Screws Bicycle Small Parts Campagnolo, Shimano, Suntour, Dia Compe, and many others.

7-speed Hyperglide cassettes are still in production and cheap! Don't worry about rebuilding the wheel yet.

Universal Cycles -- Cassettes & Cogs > All 7 & 8 Speed Cassettes