Hey Kraig and Paul - thinking further about this, and since Paul said one of the pulleys seems to have failed, I'm wondering if the pulley bearings failed because the belt puts twisting pressure on the pulley (I also noticed in Paul's pics that one pulley has a big dent).
Kraig - (one way or another I may get you to come up with enough time to test out this theory). You posted a couple pics of a wide frame mule drive and sub-frame on another thread, and I'm reposting below. In these pics you can see the angled pulleys and the sub-frame offset. If Paul could get these parts (complete wide frame mule drive with the sub-frame that has the offset) it looks to me like all he'd need to do is the following:
Switch the narrow frame hanger bracket onto the wide frame mule drive, along with the narrow frame tension spring (since the wide frame tension spring is to wide to fit). He'd have to figure out how to attach the back end of the spring which I think maybe just a matter of a longer bolt holding the pulley BUT since the pulley is at an angle that may not be the real answer.
View attachment 145192
View attachment 145193