I don't think you will have a problem. I went thru an experience when I bought what I thought was a 123 differential and had a shop swap it into my '79 300TD. It went in OK but we had a problem with the camber on the rear wheels and then the half shaft had some slop where it fits the differential. Then it was determined that it was a 300SD differential.
There are 2 precision ground spacer washers that fit between the half axles and the differential housing. Mine were the wrong thickness. I had to order a kit from MB that has several sizes and that turned out to be a long delay as they had to call someone in the shop at the local dealer and then after a lot of searching they foiund the kit number then they ordered it from Germany. It solved the problem, but I read somewhere on the SHopforum that these kits are obsolete and unavailable any longer.
FWIW, I am running a '79 200 TD with an '85 300dt engine and a W116 300 SD driveshaft modified yoke and a ?? 300SD differential. Lots of things can be done between series if you have a little know how and the drive to make things work.

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'95 E320 Wagon my favorite road car. '99 E300D wolf in sheeps body, '87 300D Sportline suspension, '79 300TD w/ 617.952 engine at 367,750 and counting!