Last pics before FMIC

[D_Eclipse9916]

Obviously you have not figured into the equation the inevitable "slack" in a drivetrain

There's nothing to "obviously" figure out. There is no slack to take up anywhere, and if there is excessive clearance then you have bigger issues.

Everything's engaged. All the time. Gears are constantly meshed, in the trans, in the center diff, in the rear diff, etc.

....................metal bends through the driveshaft, joints, axles...twisting...There is tons of slack in a drivetrain, dont show a picture of a tranny...But if you like being anal, There are "slack" between the gears and the machine tolerances are not perfect. But what I was tlaking about was connections between axles, hubs, driveshafts, joints.