proper fluid level on 727TF

The fluid level when not running is irrelevant. As was said it must be idling and in nuetral to ensure the coverter, cooler etc are full. Personally with a deep pan and corresponding spacer I am running at the bottom end (add) on the stock dilstick. This ensures no windage and aeration of the fluid, a well submerged pick up, and lots of fluid to avoid overheating . It sounds to me like you need to drop the pan, insert a stock dipstick and look from below at where the level lines on the stick are, then put in your aftermarket stick and mark it to match.