Road Racing - Oil level with cooler

I have an LS6 engine with a remote oil filter adapter. I also have an oil cooler. When the engine is off does the oil drain back from the oil cooler and the remote oil filter adapter to the oil pan? I am not sure if I have to overfill the engine with oil to compensate for the additional oil lines and oil cooler. The setup also has a inline thermostat. I'm looking for best practice advice. I usually warm up the car and then top off the level. I am having oil leak issues which I haven't yet looked into. If I am indeed overfilling, where would it leak from?

I wouldn't track a stock LS1 motor w/ less than 7qts. 5.5 to 6 was the OEM fill. It was moved to 6 around 2000 or so. Tracking the car will call for an additional qt (that is 7 now). Adding a cooler and lines will add about a qt. So 8 is a good round number depending on your cooler size, line length.
I ran 8 in my 98 Z w/ a cooler and I run 8 in my LT1 CMC2 car and it has a cooler as well.

As an idea on my C5Z, I had a 3 quart accusump (for a little while) + a cooler. Full level with that setup was 12 quarts with the top off.

The last motor was without accusump...can't verify oil amount.