The description for that tool is incorrect- - - - -it's a nozzle aiming tool. There is another fixture designed as a dual purpose tool for checking the depth the rod dipper drops below the oil pan rail, and a gauge on the bottom of the same tool that checks the height of the dipper trough below the pan rail. There are two of those fixtures, one for 216 engines, and a different one for 235's, because of the different stroke lengths of the crankshafts. Just aiming the nozzles isn't sufficient if the trough height isn't adjusted also. Some oldtime wrench jockeys would use a tapered punch to widen the opening of the dippers to give the nozzles a better target to shoot for.
Jerry
