Abstract: A diffusion printer for creating indicia in the top of the keys (67) of a keyboard, such as a computer keyboard (69), is disclosed. The diffusion printer includes a hot stamp press (11) that has a heated, vertically movable platen (15) positioned above a table (13). Mounted on the table is a double tray shuttle (23) whose trays (27) are alternately shuttled between loading positions and a print position located between the platen and the table. Each tray (27) supports a plurality of fixtures (51) each formed to receive a keyboard (69) that includes a plurality of keys (67) to receive indicia. Each fixture (51) includes a fixture base (53) having a plurality of spring loaded pedestals (65). The pedestals are positioned such that a pedestal (65) lies beneath each of the keys (67) to receive indicia. The keys (67) are maintained in a fixed position by a key cap locator plate (55) mounted atop the fixture base (53). The key cap locator plate (55) also functions as a heat shield.