Greetings. I'm interested in rigging up a limited slip differential for my US market W123 wagon that has a 3.07 ratio. One possibility I know of would be to use a Mercedes conversion kit from Racingdiffs that is designed for 185mm ring gear. The company knows it fits W124 and W201 differentials but says they aren't sure if it fits W123 differentials but it might. Apparently the flanges could be larger on the W123 and that might interfere but I'm not sure what that's referring to? I apologize that I'm not very knowledgeable about differentials so I'm unable to explain in more detail.

So my question is: How similar are the spider gear assemblies in the W123 and W124 differentials? Does anybody have any direct experience with these conversation kits and do they even work? Any advice is appreciated. Thx for reading my post.