Not my YouTube videos .....must be someone elseN249P tailwheel weight was showing exactly 50 lbs at last weigh in about a year ago. O-320, wood prop, no Landol ring. 966lbs empty.
Too many variables in your original question to give one answer but I'll give a few.
For just a mathematics exercise:
To stay in CG limits (and disregard Max Gross) with 0lbs baggage and full fuel, and my 215lb butt in the front seat, max rear pax is a surprising 335lbs to get a 30% MAC. Gross Weight of 1708lbs (my airplane is 1500lbs)
To stay within 1500lbs Max Gross, 0lbs baggage, full fuel, my butt in the front: max rear pax weight is 127lbs yielding a 22.8% MAC.
To stay within 1500lbs Max Gross, 0lbs baggage, my butt and a 250lb pax, Max fuel is 11 gallons giving me a 28% MAC CG.
I've seen your youtube videos flying with 2 up in a -4, even doing Acro, so I don't need to tell you what the rear CG feels like. But my personal limit is around a 250lb pax weight. Any bigger, and they have a hard time even getting in or out.
What's most surprising about the maths, is if the builder put the higher gross weight on the airplane, 335lbs and full tanks is within CG?!?! No thanks... haha