Good to hear about Scotty. Does he still run the duster? My pushrod lengths are different as well. I think its the way the base circles were ground on the cam. My 360-1 heads have different length int. Vs ex valves also. Check the oil galley in your heads to be sure there is not a plug in it. There located in the saddle that the rocker shafts set in. Should be one per head. Might want to turn the oil pump to be sure oil in getting up there.