I think it could be done, but like John said, the conveyor chain gear box, needs to be geared down. Since changing the gear box would be cost prohibative, going to a different sprocket and chain combo should do the trick. It may take some T&E but I think it would work fine. Is it worth it, the smith motor is about $ 250.00 plus cables and solenoid, and connectors. In the end I think it will cost as much as the new briggs, so you will have to determine if thats what you really want.
Dino