Make it super ugly - only possible way to have it for good, without someone buying it of me, as it already happened few times with those I had as mine - simply because they already been on disposal. One of cases I bought cheaply, exactly for prototypes purpose, redundant pcbs ( leftovers from protowork) used for both front and back plates, old/initial crude display. As intended to serve also as demo specimen, set of gain setting jumpers replaced with battery of relays, controlled with 5-step rotary switch at back. Title on functional display sez "SE", will re-flash later, because I evidently made it balanced - 3 SE inputs, 2 Bal inputs.
Lousy pics - Alu case elements showing bad on white background