Not quite visualizing the entire process there N.H. but I'm sure it's working for you. Maybe if you get the time you can send up some pictures.
I then drilled and threaded lag screws into the stone to hold it firmly.
Don't you worry these screws will rust and crack the stone right down there by the hole? Do you use plugs or go right in the stone with screws only? Probably if you cinch those collars down good there will not be to much stress on the screws. I have found some paper there under the collars helps them grip the stone.
Well, I have got the best part of the split firewood stacked in the wood shed too, filled right up to the nook, and today I'll be going further to get the last in while there is still a frost in the ground and I can walk there more easily than in the mud. We're looking at about 30 cubic meters to get through the winter. Had to send my young daughter up there while I passed the wood to her from below. She's getting to be a good stacker.
I sat down at the grind stone myself last week when there was a bit of warmer weather. It sits out all winter and I dare not use it when there is ice inside. After greasing the bearings and linkages up with that lard she ran smoothly and I got a few splitting wedges trued up before getting to wet from all the splashing water.
Looking forward to more on your grind stone saga. And remember, keep your nose to the grind stone