Re:
I'll have a look at the stay angles tomorrow, I'll also clean up the BB and see if that gives any clues, I think it and the M737 rear mech are quite possibly original.
It's a little odd in that a lot of the components have been changed, including at least one of the wheels and the front brakes, but the bike actually doesn't look like it has had a lot of use. The paint is knackered but that is more to do with being stored in the damp, possibly near the coast, rather than being beaten up through use. Perhaps it was once much loved and then later robbed for bits... who knows.
I'm still not certain what kind of build I will do yet, practical that is for sure as this could easily end up being a mile eater to use when I want something different to the DOGS BOLX. Very different bikes I know, but a bike that will just go where you point it with the minimum of drama is a fine thing as far as I am concerned.