i have a set of 4.56 gears out of a 1980 1ton 4x4 chevy, the front is a dana 60, no one around here is sure exactly what the rear housing is. i want to know if i can swap these into my m715, since new gears are kind of spendy. if anyone has done this please let me know. also, can you mount the pto from an m715 transmission onto the chevy 4speed? if it will not work, i will stay with the original equipment.