Just to let you know. I wouldn't suggest using a used oil pump for the sr's. I tried doing that when I popped the head gasket at the end of last season on my new stock bottom end for this season and ended up loosing oil pressure on the dyno during a pull 3 days before Import Showdown. Had to pull the motor, put new bearings and turn the crank in three days( and 1 was an all nighter). Just my