Good advice from others to "X" measure the frame.
Cut the cross member to install the drop member? You mean, removed the rivets? Very possible the frame sprang when you removed it, especially if it has been bent and straightened before.
Has the frame been cut or shortened?
Crazy idea, just for grins and giggles: Measure the loop area of the cross-member to see if the loop is in the exact center of the frame, or if it's off-set, and if so to which side it is off-set.
Read into the following what you will.
RULE 1: UNIVERSAL JOINT OPERATING ANGLES AT EACH END OF A DRIVESHAFT SHOULD ALWAYS BE AT LEAST 1 DEGREE.
http://www2.dana.com/pdf/J3311-1-HVTSS.PDF
Keep in mind the dynamics of a driveline operate on both the vertical plane and the horizontal plane, so you actually have 2 driveline angles to consider when you by-pass the factory engineering and install the adjustable pan-hard bar. It would be interesting if you could re-install your stock pan-hard bar and see where that might lead you.