Thanks westcoastech.  We'll see how this pans out.  I haven't figured out if a working 512k Hyperdrive is collectible (the purists would say that this butchers a 512k) but I think it's collectible because it is something done to the 512k that Apple didn't want to happen. They ended up eating crow and supporting it in the long run.  Sadly, the compatibility with later OSes was a problem for the Hyperdrive (as the original owners complained) but for vintage collectors, that's not a problem