Actually its a super t-10 I have done several Muncies and Saginaws over the years but this was a little different with the needle bearings, I made a shaft that was 10 thou smaller in Diam than the cross shaft and 1/8" inch longer than the cluster so it would go in the case and hold the Needle bearings in place, then once I was ready I pushed the countershaft in pushing my new one out and it worked great
here's 1/2 the needle bearings ready to slide in

and all back together

 

I just pack mine in with grease on the inside of the countershaft. Although last time I did it, I had 2 leftover bearings. Took it apart, counted, discovered they sent 2 extra bearings in the rebuild kit.....doh. I count them beforehand now.

 

Nice job. Did you go with torque lock sliders?