I'm slightly amazed at how some eBay sellers react. Take this item:
which the seller had listed as a 'PDP-8 PC05'. I sent the person a message
pointing out that it was a PC04 (as shown by the 4 rocker switches, and the
small backplane - PC05's have a larger one to hold more cards).
They sent a nice peply, but didn't alter their listing!
Well, I hope the bider really is a PDP-8 owner who wants a PC04... :-)