Gordon writes: Go too far down that road and you just have a KL10 cabinet with a PC-clone emulator inside. At which point you may as well have kept the KL10 original and just had a PC-clone running an emulator too. Seeing as how the major operators of KL10's in the 80's were already retrofitting switchers in, I don't think that putting switchers in today would be the worst thing to do. But I bet the KL10's owner went out of his way to find one as original as possible, possibly passing over ones that had been retrofitted 15 or 20 years ago. One of the most enlightened attitudes is that since all 10's after the KI were already emulating (via microcode) a PDP-10, why not just do the emulation on a little PC-clone and call the operating system and emulator package "microcode"? Tim.