I am facing the same situation with an 85 300SD. I was going to upgrade to the newer axles but could not find the stub axle to install on the differential so I decided to clean, grease and reboot the original homokinetic axles.

I so far have not been able to get the axles out of my car. They will not compress enough to clear the wheel bearing. Does anyone have any suggestions for this increasing the clearance?

Also I found a product by Dorman UNI-FIT and Multi-Fit that are supposed to allow installation of the boot without disassembly. Part number 614-040 and 614-050. Around $75 saw on their website.