The new nuts are about $2.50 at CarQuest in my neck of the woods.

When I still had an auto transmission in my W123, the tailshaft housing had a big chunk broken out of it. I removed a donor housing from a transmission still hung under the car, and someone had already turned that nut round. I slotted it with a Dremel cutting disc on each side, and popped it loose with a hammer and chisel pretty easily. You can still get that nut off.

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- K.C.Adams

'77 300D Euro Delivery
OM617 turbo / 4-speed swap
404 Milanbraun Metallic / 134 Dattel MB-Tex

Current status:
* Undergoing body work

My '77 300D progress thread