I'm no expert by the way, could well be an F that's had parts fitted from later models ie the carbs & fairing . F has shorter swing arm 23 inch if I remember correctly but they could well have been changed too, best check numbers to be sure.
Welcome, plenty info if you have a look through projects section. Are you sure it's an F looks more like a G to me, it has jap clocks so could be a mistake when it was imported/registered. My F (import) is on a C plate an d my G is on a B plate
I haven't but if you have a look at katanamangler & cockneyricks build threads you should get the info you're looking for. Or look at parts diagrams on CMS or Robinsons web sites.
Carefully heat the bolt with gas torch then pour plenty water over it. If you don't have access to gas torch Wurth do a realy good release spray but can't remember what they call it, good stuff tho