Today we installed the 1957 rear end in the 1955 frame. I think my daughter might be getting the hang of this rebuild thing. She still has some trouble with hammering in the axle but overall did a great job.
The '57 has a drain plug in the bottom of the housing. We are also running Disc brakes, 370 gears and new posi traction unit, and we installed the New Big Bearing kit from Tri-5WeeCrafted.com. We have replaced the bearings with new 58/64 axle bearings. Still need to install the rear sway bar and rear shocks. Front end will be put together next.