I noted a previous post about adjusting 741 valve clearances and I use a shortcut on my Chiefs which could work on Scouts using the same tappet (push rod) bolts. Rather than fiddle with a feeler gauge and several wrenches (you almost need 3 hands) there's an easier way. The bolt at the top of the tappet is a very fine thread and one full rotation is equal to .030" travel. Each side of the bolt's hex head represents .005" movement up or down. This is in the middle of the .004" clearance for intake and .006" for exhaust valves. Snug up the tappet bolt to the valve finger tight (with the cams in proper position) and then back off the bolt one side from that position, either a little less or little more to get very close to the proper clearance. Then you can easily double check the clearance with a feeler gauge.