With only 40+ years experience of working with stainless I hardly dare add any advise

Stainless comes in many specs, some are just a bit more 'difficult' to drill than mild steel, some are a lot more difficult and for the home hobbyist could be a real bitch. As above, you need to centre dot the hole, FFS don't use a flat bottomed cutter in a drill press, cobalt drills are good to use but HSS will probably suffice, your mains drill will probably be too fast, if you have a battery drill this might well be better, as it's a one off use whatever lube is to hand, duck oil, engine oil, or grease.