Can anybody help identify this piece (2 pcs.) that go together, which I believe to be a part used in antique printing process / plate? it is two pieces with missing "bolts" to clamp the two pieces tightly together with wing nuts? also, noticed some faint text residue as in newspaper column imprinted faintly onto shiny presumably nickel plated surfaces? this item has really got me stumped?.. it has part nos.? like many old coal fired or wood fired stove/furnace parts have by various makers