Hi,
I did mean the Z3 card rather than the other versions that plug onto other cards. Why didn't they change the name to make it more clear?!
Anyway, thanks for the info Doobrey. I plugged the card in with the components face up, closed my eyes, took a deep breath, pressed the power button of my dear Amiga and, with a flash of lights it booted straight up. Phew! So thankfully no dead motherboard and no scrap Hypercom Z3 either.
If it had been a PC it would have blown up whichever way I installed it just to spite me...!