I welded my e-track to the floor, less chances of screws ripping or vibrating out that way.Better to be safe than sorry.Flying freight is not a good thing...12"x1/8 thick steel plate in front, against the bulkhead wall, keeps the freight from hitting the bulkhead wall, and 12"x1/8 thick steel plate along the sides keep the freight from hitting the wheel wells during loading and unloading..E-track is 24" apart from one another, that way, small skids can be strapped down as well.So many place their e-track on the outside of the cargo area, with this huge gap in the middle, so strapping small freight is diffcult this way.I willl use aluminum next time,instead of steel to save weight.