Hello,
I have finally read this entire thread and all links that address the 051 to 075 conversion. I think it is my understanding that the early 051 cases are hard, maybe impossible, to convert due to the 2 openings in their cases that fall outside the footprint of the 075 cylinder base. I suppose that the tabs or flanges on the 051 cylinder bases cover these. I have not only found listings on eBay for 075 compatible cylinders that have these tabs, but the Cross Performance 075 cylinder kit on HL Supply appears to have them as well. Does this mean that earlier 051 cases are now viable candidates for the conversion with a simple 6mm tapping and all 075 parts listed before here in the thread, i.e. muffler, studs, etc? Here is the HL Supply product page and a random eBay listing. Is there something I am missing? Is the case difference really matter? I am new to this, but my grandfathers old saw from the early 70s is coming my way and I would like to get into milling. I appreciate the time to read this much.
Thanks again
Cw