123 to 116 differential swap?

[ferreed]

I have the chance to pick up a differential from a '79 300CD tomorrow for my '79 300SD, so I tried to read up on diffy swaps. There was some mention that shims might be needed in order to keep from leaning the tires out a hair and affecting tire wear, but there were other posts that seemed to indicate that the swap could be made with no problems without shims. Can anyone out there relate their experiences doing this swap? (i'm not worried about the higher ratio, just the actual fit and functionality.)

Thanks!