I just finished installing a Novak Dana 300 adapter in my SM465... Fun stuff.
I got the rear mainshaft bearing to pop off with 2 big screwdrivers. The rear countershaft bearing was another story... Took it to a tranny shop and they broke their puller on it. Finally got it out by using an air hammer to remove the little metal ring that spaces the balls in the bearing, then using a dremel to grind a relief in the races so I could remove the balls one at a time. After that removing the rest is a piece of cake.
The Novak adapter kit is awesome, their instructions suck, however. The Rebuild kit is pretty good, too. I found several factory rebuild manuals on the web, I'd be happy to email you what I have. I found a couple versions, unfortunately one is missing a page, but you can get by without it.
My advice is to read through the manuals several times before you start, so you can get a feel for how everything works together. Keep your parts oriented so you know how they fit back together. Taking pictures as you disassemble is invaluable when reassembly time comes. It's actually a pretty easy job, and you feel great when you get it all done.