Can't say for sure, but I am almost positive the large pulley would hit the seat pan. You do have a sawzall don't you? Just kidding. I would look into using the idler pulley arrangement from the newer style and changing the pulley size on the tiller. That might work.
I think there was a kit for the newer tractors which had a pulley in the rear and you use the clutch in the mid-pto. Since you have that clutch, you didn't need the two pulley setup with the clutch... only the FDT's need the clutch setup (I think).
Well, I figured the sheave would be too big... I think I have seen tractors with a slot cut for the pulley.. The catch is that that arrangment is necessary to achieve the double reduction necessary. To achieve the same reduction with one belt you would have to have a pulley the size if a wagon wheel on the tiller. I do have an extra seat pan and an old seat. I could change out the pan when I till. The reduction ratio would still not be as low as with the FDT's since the sheave at the BGB is larger on the cone clutch.
what If I could drop the large pulley down on a low bracket then have a short belt to a set of pulleys on the pivot rod and a belt going from the set of smaller pulleys to to tiller. Please pardon my sketch. I lost my computer last week and had to buy a new one to run my business software on. Unfortunately all my 10+ year old programs to include my accounting software and Cad program are not compatible.
Phil
"They that can give up essential liberty to obtain a little temporary safety deserve neither safety nor liberty."