Royce: Ball location of 1" sounds ok. A more important consideration is how much travel the ball has in its port area. When I built mine I found it worked most dependably when it traveled 1 ball diameter or less from its seat. You want to perform all pressure/leak/output tests by hand before mounting on the chassis.
Priming: without a tender pump for priming the axle pump you should open your bypass and roll the engine back and forth monitoring your return line into the water tank (engine cold). You will see an air/water mix at first settling down to water once the air is purged. If the chassis is too stiff to do this cold then perform same procedure during the initial engine warm up period. Remember the pump draws additional horsepower off the engine, you may find you need the bypass wide open until the engine is warmed and cleared. Jim
