Okay, I can see the photos now. Based on the ID tag (which does not have a -1 or -2 suffix, and whose center three digits are 000 instead of 001 or 002), and the aluminum side plates and rear cover, I'm fairly convinced that what you have is a first-generation ZF gearbox, as originally developed for Ford by ZF for the GT40. It has tremendous collector value to the owner of any original GT40 who is seeking to keep his car original, but from a practical perspective it leaves much to be desired, when compared to the later ZFs which incorporated a host of improvements, and (in the case of the Dash-2) were mass-produced, thus guaranteeing continued parts availability.
Its value would be difficult to ascertain. Given that a run-of-the-mill Dash-2, with unknown history and thus probably in need of an expensive rebuild, is a $4-5K proposition, a Dash-0 in similar shape could conceivably be worth a fair bit more.
There is a UK specialist for these gearboxes, who has rebuilt well over a hundred of them over the years; his name slips my mind at the moment! If nobody else comes up with it before tomorrow, I'll have it by then and will share it. He will be in a much better position to offer up valuation etc. and could perhaps help you find it a new home, if that's your ambition....