UPDATE for the creeper.
after a bit of a wait. i got to run the creeper again. for the past week i have been testing a locker that is custom made for the creeper axles. all is going good and the part seems strong enough for the beating i have been and will be putting it through.
here's a peek of the prototype.

the final parts may look slightly different but will be just what i needed to bullet proof the creeper axles.