say does your adaptor plate have an extra jackshaft on the rite side  or does the shaft coming over from the head drive  run the snapper head directly ? reason for asking  tryed putting a snapper head on my 3970 but had bad problom with chains jumping an tearing . was a major fiasco ! now after looking at some other jd chopers an saw that setup i wonder if the head was running to fast ? anyway my greenspout 3970 with horning kp an snapper set up is forsale