Fwiw...... for what the OP is doing with the motor, I would have used the HV pump from the start.
I use a HV pump on anything other than stock pan engines. They have a tendency to run stock pans dry, which is never good
I've heard this many times and as long as I verified that the pickup was within 3/16 from the bottom of the oil pan(through the drain plugs) on stock OEM 4,5 and 6 quart stock pans I never saw that happen
I have seen it happen on a motor with a 7.5 quart deep sump pan that the owner used the "correct' pickup that came with the pan that was right at 1.5 inches up from the bottom the oil pan
It would loose oil pressure at the end of a 1/4 mile run when he let off
Murphy lurks waiting to mess with us car guys, especially drag racers