[M0FYA Andy]

Some useful advice here, many thanks. The Forstner bit looks interesting, I don't have any of those, I suppose because I've always been happy with flat-bits for drilling wood. It looks like a cross between a drill bit and a hole-saw!
Jim, an interesting comment on hole-saw pilot drills. I have a set of Starrett hole saws, I think the drill bit can be removed from the arbor.
It looks like a bit of experimentation is on the cards. I can hold the item securely, I have a machine vice with X-Y movement on my drill-press, or I can use my milling machine as a drill-press, this does have the benefit of electronic speed control (although at slow speeds it lacks 'grunt')

Andy