proper fluid level on 727TF

You cannot "remove the dipstick from the equation" because that's its job. The dipstick will read the SAME even if you have a pan a mile deep.

With stock transmissions my rule of thumb is fill with two gallons, start and run through the gears and start checking. A deep pan might hold a quart or two over that two gallon starting point.

You're making this way too difficult.