We have also designed a set of mounting feet to accompany these sliders. The mounting feet work with both designs and come with the hardware to secure the slider to the feet. One of the reasons we designed these mounting feet was to aid in the installation of the slider assemblies into your build. These mounting feet attach to a flat surface not a round tube; so it’s a lot easier to get mounting brackets welded into your project. The other advantage is, that if for some reason all the mounting surfaces are not completely flat you can easily ad shims under the pads to increase alignment. The mounting feet are secured to your vehicle by 4 ¼” bolts.