You can get a hot-shoe adaptor very cheaply that will connect your flash to the Mamiya, fits the bottom of the flash and has a lead that plugs to the synch socket, you might want an extension lead as well.
A 1/60th's never been a problem when I've used flash on my 645's it allows fill in if necessary as well.
Hi Ian, I've been looking for the adaptor with right lead but I'm clueless as to what i need. I was on Adorama site and for the life of me I can not find what I need. Possibility you can point me to a picture or a link?
Yes, I also like ambient fill, however, sometimes I would like more synch time around 1/200.