The real questions are these. Is it worth repairing and is it economic to? After all, you've already purchased a replacement - so why bother repairing the old one? Are you going to spend money on the old one just to see it wasted as it's sat in a cupboard waiting for the new one to fall to bits in X years.

Reminds me of my friend locally who has a garage full of used but rebuilt MGBGT assemblies..... just in case. A totally rebuilt complete front chassis crossmember, an o/d gearbox PLUS a rebuilt o/d unit, back axle PLUS a couple of crownwheel and pinion variables. Pedal box with new cylinders..... Anyway........

Yep, it could be repaired but to achieve what?