I have small coin boxes that measure 6 inches wide by 11 inches tall. To accommodate the Crytopay card reader, I was planning on mounting the display timer on the wall above the meter box and having new faceplates made. The box is recessed into the wall approximately 3 inches. What would be considered the minimum required clearance from the top of the card reader to the top of the box. would 2.5 inches clearance above the card reader be sufficient clearance? As a second option, I could also mount the reader between the upper and lower openings for the coin acceptor. (I saw this setup on the Crytopay website). If I went this route, would the card reader interfere with the insertion of quarters? Would quarters get caught up in the reader slot? Any ideas would be appreciated.