closeup sideview of front foot. Had to angle each caster 10 degrees, used a bandsaw to slice a 1/2 inch thick ALU plate corner to corner to get the slope. Then bolted each caster to the mounting plate (scrap fiberglass) with the wedge in between. Snug fit, but centerline of casters even with bottom edge of Krider ALU footshell - same as left and right foot drive clearance. Angled front and rear help this center foot over door thresholds - and stable two point mount.