Driveline angles changes in a drop

[gkesseru]

From another thread I was directed to read the importance of minimizing U-Joint angles changes in a driveline system.
see http://www.drivetrain.com/parts_cata..._problems.html

Using this info, it infers that when you drop the rearend you should also raise the transmission mount and the front pivot point of the trailing arm in a coil spring suspension to keep the u-joint angle back at 0 degrees. (for leafs they recommend shims)

In my 68 shortbed, the trannie mount is 38" from the engine mount and the rear axle is 112". The front trailing is 49 1/2 in front of the rear axle centerline. Doing some quick calculations, for every inch of actual drop in the rear I should raise the trannie mount point .34 inches and raise the trailing arm front pivot by .44 inches.

For a 4" drop therefore I should raise the trannie by 1.36 inches and the training arm front by 1.77 inches.
Are there any frustrated engineers out there that agree?