FINALLY have the MG back on the road after I quit dragging my feet.
Total list of things done:
Remove all rear suspension components
Clean/sandblast and paint all brackets
Replace suspension hardware
Replace suspension bushings with polyurethane bushings
Remove hub and brake backing plate, sandblast, paint.
Replace hub seal
Reassemble brakes with new cylinders, adjusters, and hardware including springs(ebrake lever reused, so cleaned and painted)
Reassemble hubs
Drain differential(tip-do it more often than once every 50 years-the oil is nasty)
General clean-up of differential, clean and sandblast cover and plaint
Reassemble with new gasket. Note that MG axles require GL-4 spec gear oil, which you most likely won't find at your local auto parts store. The current spec is GL-5, which is listed as backwards compatible, but the thrust washers in MG axles are bronze and GL-5 doesn't play nice with yellow metals
Fill with gear oil-Sta-lube 85W90 GL-4
Derust and paint rear axle
Remove old brake lines and flex hose to rear axle
Cut and flare Cu-Ni tubing with the proper bubble flares and fit with Girling type flare nuts(not easy to find, but there's a GREAT supplier for anything brake related I found)
Route tubing and secure with clips and clams as appropriate
Bleed brakes(surprisingly stubborn to do)
Disassemble Armstrong lever action shocks
Drain 50 year old(nasty and smelly)
Clean shocks by flooding and working fresh oil through
Reassemble
Fill with the correct amount of the correct oil. There is expensive shock fluid out there rated at SAE 20 which works, and is about $15/qt. On the advice of the Armstrong shock expert, I bought a 2 gallon jug of AEW68 hydraulic oil for $12 at Rural King. Filling is a surprisingly fiddly task that involves filling most of the body, sealing it up, then fill through the valve port while slowly working the arm back and forth to be sure the oil is everywhere it needs to be and there are no bubbles. This is tedious as working the arm too fast can introduce bubbles, and working them out too fast also cause oil to either spit out or foam
This turned into a lot of work, but I shouldn't ever have to do it again.
BTW, this is all under the category of "maintenance" and not "Breaking down", even though I've been accused of the car "breaking down a lot" in this thread. Old cars need more routine and preventative maintenance than new cars(find something in production where you actually take the shocks apart rather than just buying a replacement you drop in) and while doing other tasks sometimes it's worthwhile to do other things with unknown history or while access is easy.