Front hub OLD has commonly been 100mm forever, but there were a lot of bikes with 96mm made in the '60's, IIRC. My advice to you would be to:
1. check your frame for straightness.
2. Spread/cold-set/align your fork and rear dropouts to the widths that will fit your chosen set of wheels.
3. align your front and rear dropouts.
4. align your derailleur hanger.
If you don't know how, there are lots of YT videos on how to do this, many of them show you how to do it without using expensive proprietary tools.
This can be done, easily with a little work and attention to detail. Here is an old Dunelt that I "hot-rodded" a few years ago.
Some guy bought this and rode the entire Pan-Mass Challenge on it. Here's the build-link:
https://www.bikeforums.net/classic-v...urrection.html