fred wrote:

there is no need to run anything but a
taper for 2mm material with plenty of clearance behind.

Thanks, makes sense

I'd be a lot more worried about using cheese type HSS taps in stainless
for a bottom hole but I would certainly have a go with one on thin
material.

I find it odd that they only specify suitability for "some" stainless
steel, without saying which

http://www.cromwell.co.uk/SHR0850330A

I presume 304 is less hard than 316?

With cobalt drills being so reasonably priced these days I would buy 2
or 3 for the job, just in case, they will make it sooo much easier

Yes, I always bargain on a having couple of spares for small diameters,
had already put some cobalt ones in the basket.