Old MOS Mask-Programmed ROM forgetfulness?

It is interesting, I have 1702As that were programmed in 1973 sometime and they still have their data ( used on my SIM4-01 ). And yes, I have them backed up. It is interesting that Data I/O has added supply current checks. I've used many home made pin adapters over the years to read old ROMs, as John probably knows, as some were from pin ball machines. Some of the earlier ROM also had address latches built in, making reading tough. Anyway, making pin adapters is not that hard. I usually stack a three solder pin, machine pin sockets. In place I don't want any connection, like Vpp, I pop the pin out. In other places where I need to rewire, I break the solder pin off and file it down a little so it won't short. I do connections and sometimes vector side boards with soldered wire wrap wire. Often I need switches or sometimes logic off to the side. It only takes 15 or so minute to put a typical adapter together. Dwight