I finally got that stubborn inner bearing out; I eventually punched out the inner race, leaving the outer race stuck within the bore. Then used a chisel and some PB Blaster to penetrate and get the outer race out. I had to actually put the machine on its front with 2x4s and knock it out that way. I did manage to get the new bearings in. I froze the new bearings, then drove them in with a punch and hammer. The other issue I had was making sure the bearings were aligned and straight. Even though I drove them until they hit the shoulder of the bore, the spacer would push tightly against the bearings, making the bearings bind and impossible to turn. So i used a punch to adjust the rear bearing so it's slightly out further than usual.