Milling coffee table maple slabs

A co-worker asked if I could mill flat two coffee table maple slabs both sides, I was thinking how am I going to hold the down on the spoilboard. I came up with the idea of making two biscuit slots on each end, which he was going to cut off. I laid the maple slab 24″ x 44″ x 3″ on the spoilboard and using wooden wedges I was able to level the slab to get the most yield out of the material.