Re: narrowing a dana 44 front axle
If you want an SOA front end, what you're proposing is about the cleanest way to do it. If you want SUA, then a different housing would be the better place to start. It's tough to find a 65" D44, tho. Most of them are either the full size like your Chevy one or are shorter, like 58 to 60. Narrow track FSJ D44's are a good place to look for a 60" SUA housing.
As far as the actual cutting, it's not that bad of a job. Grind the weld out that holds the inner knuckle to the tube until you can see the parting line all the way around it. Then drive the knuckle off. It's not easy to do, but it will come off. Some penetrating oil and sometimes some heat helps. Once it's off, cut the tube to length and clean up the end. Then drive the knuckle back on. It will be necessary to clock it correctly for proper caster. If your other side doesn't have proper caster, then you'll have to do the same on the other side, too. Once the caster is correct, you can weld the knuckle(s) back on and reassemble it. you'll also have to do something with your tie rod. Mine turned out to be 1" dia solid steel, so I was able to just cut it off and rethread it. Some are hollow tubes. Those will take a different plan. Depends on what you come up with for parts.
Moser and Dutchman can shorten and respline the shaft or can supply you with a heavy duty replacement shaft in the correct length.
"If you didn't build it, it isn't yours . . ."