I decided to go ahead and plate the bottom of the front rails and was thinking 1/8th should be enough added steel I used that mostly because it is easy to make a ghetto brake and form it to rail shape .XJ is on built tons 44's full hydro linked caged ect and that is why I figured I would plate more than the usual production set of stiffeners allow . I can easily make a second set and plate over them.for a 1/4 plate thickness , but if the consensus is .125 is adequate no sense in addi.g more weight