W123 and W126 axle difference
 

Hi
Can anyone tell me how to spot the difference between the W126 and W123 axles (1984) they both have the Homoklectic (SP) joints and the sleazy fellow who sold them to me told me that there was no difference but when I try to cross the part numbers there are none for the 126 /???? I would like to know before I take the differential apart to get it in and find that it will not fit.
Thanks
Robert

I believe they are interchangible. There were some differences in construction through the years but I believe they all interchange.