High speed driveline vibration after readylift

[BoostedFX4]

Truck is a 2015 f250 short bed, single peice driveshaft, 4x4. Installed a ready lift 2.5 inch stage 3 level kit. Used the provided tapered 4 inch blocks to replace my stock two inch blocks. I have since developed a driveline vibration that occurs past 40mph and only under hard throttle, once I release the go fast pedal it goes away. Is this something I could fix with a non tapered block or will I need traction bars? Also slightly off topic but is a adjustable track bar necessary if I did the track bar drop? Any help would be greatly appreciated.

 

[sootie]

if the vibration is only under heavy acceleration, traction bars should fix it.