Quote: my bets on the pickup is to close to the bottom of the pan.
What makes you think that? I run the stock pickups on the bottom of the pan like the Mopar FSM recommends, no problems ever Car runs low tens, high nines shifting at or above 7000 RPM on every run with the stock 3/8 pickup and 6 quart Mopar OEM pan for the 1970-71 Hemi/440 6 pak motors, 5W 20WT Valvoline non synthetic Take a hard look at the stock pickups and go from there
pickups tubes are adjustable, and if they are to close to the bottom of the pan it will cause exactly what the op described.
makes no difference what kind of pan or pickup,it needs clearence to pull lube in under it
to high in the pan will do the same thing , as it'll start sucking air
Car runs low tens, high nines shifting at or above 7000 RPM on every run with the stock 3/8 pickup and 6 quart Mopar OEM pan for the 1970-71 Hemi/440 6 pak motors, 5W 20WT Valvoline non synthetic 
Take a hard look at the stock pickups and go from there 
