As for finding detailed instructions, it can be tough. The best write up I was able to find was on Pirate under the tech section but it is for a 14 bolt and a 60. It's written by billavista. Obviously 44's, 14s', and 60's are not all the same but the articles are detailed enough that you can figure things out. I didn't find the Yukon manual terribly helpful. And another thing to keep in mind is that not all 44's are set up the same. For instance, many use a pinion baffle and slingers, but not all. Just set it up the same as the one you take out and you'll be good.
Although it is confusiong to read about, once you get in there and start identifying parts and using the correct terms it starts to make sense. As for difficulty level, it's not really hard, it's just precise and requires ALOT of patients. I prolly put and pulled the carrier from my 44 3 or 4 dozen times. I only ran the pattern 5 times, but I adjust tons of other stuff a ton more than that. You'll spend some cash on the tools needed too. I bought inexpensive ones and I prolly have around $100 or so into them. Still way cheaper than paying someone.
As for the carrier situation, I ended up getting a new carrier because I thought I was going to go with 5.36 or 5.89's (ended up with 5.13) but you could easily get thick gears as long as you're 5.13 or nurmerically lower.
A whole Master install kit can be had for around $75 and I'd say just do it. Once you set it up you'll see that it's not worth the $75 savings to have to do it again for new bearings even if the setup for bearings only would be way easier.
I'm definately not a pro but I'd be willing to try and answer any questions you have, feel free to pm me. KillerB was a wealth of knowledge too.