I bought a used Bear B52 two post hoist. This is the same as a Hydra lift. I am in the process of installing it. According to the manual, it should sit flush on the floor. But mine sits 1/4" up off the floor and when I look underneath the cross bar, at each end of the ramp that you drive over, there is a steel plate about 3 inches wide by 1/4" thick. This is what the entire hoist is sitting on, and it causes the cross bar, and the outriggers that bolt to the floor to be 1/4" off the floor. Is this normal? Do I just put shims under the 8 outrigger bolts? Or cut some rectangles into the concrete under those plates to allow the hoist to sit on the floor surface?

i am not an expert. with that said, if it were mine, i would cut the concrete surface so the entire pad would sit flush.
this is just MY opinion on what I would do if this lift were mine.
smarter people than i will steer you straight as to why the pads are constructed this way.