Or pull the test port plug and let it squirt.

Yes, recessed in the bellhousing by around an inch. The precise measurement can be taken by measuring the distance the converter mounting bosses on the flex plate are behind the engine block bellhousing flange. Straight edge across the flexplate and measure with a rule to the flange. This check is GOOD insurance. Converter should sock up to correct depth in 3 (THREE!) distinct steps, the two sets of splines and the engagement of the converter tube slots to the oil pump gear ears. The last one is the gotcha...