How to mount driven axles

[BenB]

Last year our team used 4" diameter wheels and the bumper zone was 2.5"-8". We were able to mount the bumpers above our axles, so we were able to mount our axles using collars on the inside and outside of the frame.

This year, the wheels are larger and the bumper zone is shorter, so we will have to mount the bumpers on top of axles. Using a collar would interfere with the bumpers (unless we added standoffs).

Does anyone have any suggestions how to mount a driven axle that minimizes the amount it protrudes the outside of the frame?

I have attached a picture of last years driven axle mount. Any pictures or links would be appriciated, Im a visual learner.

Thanks