I looked at the BT that I had and found that I could modify it to the design I was contemplating. Everything worked as I had hoped and the converted unit works very well. I did not take as many pictures as I should have but I will try to explain how I got the parts to fit.
The first operation was to mill the keyway in the turret. Once I had it centered it was a simple matter to mill the slot. I opted to make the keyway .100" deep so as to have room for fitting the axle length. Next came the axle.
When I made the axle I left it long so I would have extra material to clamp in the mill vise. Although it was not in my original plan I found that I could assemble all the pieces on the axle without removing it from the mill. I started by making key .060". I then assembled the parts and, using a feeler gauge I found that the axle was about .020" too long. I pulled the base and turret back off and set the "Z" axis to remove about .015". My plan was to get very close then use a shim or shims to bring it to a snug fit. Imagine my surprise when, after reassembling the unit, I found that I had about 6 to 8 pounds of drag with the center bolt tight. This was just a bit more than I wanted. I remembered reading in Ralph's thread that he has lapped the turret and base for a smooth operation so I gave that a try. I did not have any lapping compound handy but I did have some rubbing compound used on automobile paint. I decided to try that and it worked very well. The turret now turns smoothly with approx. 3 to 4 pounds of drag. I am unable to find any looseness and, turning some hard stainless, there was chatter. Guess you can tell that I am very happy with the result.
Here are some pictures of what I did. BTW the turret had two holes to provide access to the mounting screws similar to the one Ralph made. I found the hole size was just right for a 1/4-28 thread and I had a couple of 1/4- 28 X 3/16" set screws so swarf getting inside will not be a problem.
