I used this tool to fit sim-rings on an Audi A6 C7 sport-differential. The original tool VAS T40221 was not correct for the depth so I mad a similar tool to use. The installment is very good with this tool and you get a perfect alignment. I suspect this tool can be used on several Audi and VW cars (if the tool name appears in the manual).

Please print with the handle down to get a smoot surface for the sim-ring. The version 2 is recommended to use with less problems for printing over-hang. I included the version 1, that looks more like the original tool.

I used 20% infill as a first try, it worked. But it might be good to increase and/or try a stronger material if you going to use the tool many times.

I included the inventor file, so is possible to change the depth easy. Measure the depth on your differential or gear-box and change if needed. Remember to multiply by x10 when creating the 3D file.