A standard technique for positioning countertop laminate ("Formica") is to put contact cement on both surfaces, let dry completely, and then place a sheet of kraft wrapping paper on the base. Ideally, the paper will cover all but a fraction of an inch at the most critical edge or corner. The laminate is placed on top, and positioned carefully. (The small amount of adhesive that bonds is weak enough to be error correction.) Then the kraft paper is pulled out, and the bond made progressively from one side to the other to prevent bubbles.
It think that for something as small as a tripod top, I would use waxed paper or even silicone release paper to do essentially the same thing.
I just cut a square of cork a little but bigger than the plate, glued it down with contact adhesive then trimmed it flush with a razor blade. An Exacto knife blade cuts the center hole quite nicely.