TF 904 Upgrades

Where do i start... I started with a 77 non locker. After finding it had 3 pinion planetary from and rear I pulled the 2.74 low gear and 4 pinion planetaries from a 79 lock up. Drilled 1 1/4 holes in the sun shell to lighten it. Removed the governor and dead weight on the output shaft. New stock sprag and rear support. Drilled evenly spaced 7/16 lightning holes around the low/reverse drum and direct drum. Billet aluminum forward drum and hardened input shaft from A&A with tan frictions. 5 tan frictions in the direct drum after machining the pressure plate down and playing with snap rings. Also used the reverse wound spring from ATI. Split low/reverse band and kevlar direct band. 5.0 lever. Spot weld a reinforced plate t the band strut. Tossed out 1-2 accumulator spring. Removed rear servo spring and locked with shims (washers). Deep aluminum pan with reusable gasket and reusable big brass filter.
Were you running the stock input shaft when you broke that drum.
I cannot believe you broke that drum before you broke the stock input shaft. What valve body are you using in your trans.
Any sprag trouble at your power level?