Originally posted by Wild Mark Hasselblad mounts or registration distance relative to Pentax 645
There are a few Hasselblad mounts:
Hasselblad Xpan has a registration distance of 34.27 mm (bayonet)
Hasselblad H system has a registration distance of 61.63 mm (bayonet)
Hasselblad 500/2000 has a registration distance of 74.9 mm (bayonet)
Hasselblad/Kiev88 has a registration distance of 82.1 mm (multi start thread)
The Pentax 645 has a registration distance of 70.87 mm. So, theoretically, the last two on the list could be adapted.