The International Cessna^® 170 Association

Mark,
The cases are the same. When they're assembled, a starter pinion shaft is installed between the case halves on the earlier models using a pull starter. Starting with the "D" model, a bushing was installed in the same hole between the two case halves. the starter being a different type was engaged by a solenoid activation. The essential difference between the earlier models and the "D" model being the accessory case with the new type starter and a vacuum pump drive in conjunction with the starter housing casting.

I hear ya! I was told by the shop in OK that I sent the c 145 crank to that it could not go in an 0300D case? TCM said the same when I inquired. The combination had run for years that way prior to me purchasing the plane. I did not want to go through the paper work and time TCM expected it to take, so "swapped" for a case that made it "legal". The money was the same for me so I went by what TCM said.
Just my experience. Mark