Mine is a later frame, the one you posted is a few years earlier from my research, though it's really hard to date Bradburys frames as they have no serial numbers. As I have understood (or my memory serves me correctly) he made frames up until '94 even after he had licensed Manitou to Answer Products.
The bike came with a tatty M900 groupset so I went with that decision, plus I had a really clean M900 groupset and I don't think it looks out of place on this frame.