please keep the off topic comments out of this thread guys.. unless its a bump .. hehe thanks =D
back on topic.
It looks do-able.
One side of the bushing.

The other side (which shows some depth as what can be filled in )

Twisting with a screw driver to show the flex movement.
Yet i know the flex test probably really isnt much useful since I cant really imagine the subframe twisting at an angle on the car. But Im pretty sure that it can be filled. As long as I dont have the stuff pertrude any further then the metal bushing then it shouldnt have any fitment issues... this mod im hoping would add to complement the usual sub frame spacers.