Well. I think I got it. Looks to be reasonable. Won’t know till I start working it. The idler pulley is sitting in the middle of the belt and does not wander. Used the smaller in diameter but narrower pulley. I would rather use the bigger pulley, but it was very close tho the shaft pulley and engine pulley. No room for error and vibration.
So I have learned from this is, the original idler is suppose to be a V pulley and is suppose to pull down on the belt. When I got the tractor 15 years ago the tiller idler was a flat pulley and was pulled up on to the belt. So someone changed it at some point. I think I rather the pulley pulling up, it wraps more belt around the tiller and engine pulleys, so it may not slip as easy.
I have also learned, it’s very annoying that some thing so simple took two days to figure out. Should have been a 30 minute thing to do. Any way, thanks for all the help.
Noel