driveline vibration - getting worse

[max427]

93' fullsize 302 automatic 3 speed OD with shift on the fly xcase.

about 3 weeks ago i started getting a slight driveline vibration that felt like poss u-joints. the vibration is only under torque, only at high speeds. its unlike any vibration ive heard before. its only from 40mph + under torque. but when i nail the throttle to pass, it goes away. the vibration also varies in severity according to conditions. it doesnt always do it. at a steady 70mph cruise its fine untill i get to a hill or have to pass. the pitch of the vibration also changes, once it starts giving it a little more gas makes it worse untill the truck downshifts and then it goes away. it feels like its right between the motor and the trans, but i could def be wrong. i hope its not a trans input shaft endplay issue because i dont have the money to dump into this truck.
any help would be useful.

other clunks and noises i figured id mention despite that i think they are unrelated. 2 distinct clunks leaving a stop sign, one clunk when stopping. sometimes theres a tapping type vib on the drivers side that feels like wheel hop or something but its intermittent.

[rhandwor]

Pull the cover and look at the flywheel bolts to the torque converter are they tight. Look with a flashlight at the bolts from the motor to the flywheel. I have tightened them with a long thin wrench doing one and rolling the engine.
Also look for a cracked flywheel.