Well I thought I should update with what little progress I've made with my project.
The end.
Well, nearly. Anyway, it started out as a '78 F2 and in all honesty I'm not sure I had a fully formed plan at the start. I wanted to create a bigger version of a Yoshi 460/4 I built back in 1981/82. I've got it completely stripped down and identified parts that will need to be replaced (for example the rear brake master cylinder is knackered etc etc). I managed to get hold of an alloy fuel tank, oil tank and fairing from a P&M race bike from the same era. The fuel tank was made by the same guy who made P&Ms tanks and has been modified for extra range for the IOM and the fairing has a letter box opening for an oil cooler. I've also just got a replica P&M seat from Ragged Edge Racing (highly recommended btw).
So, overall, the plan is forming to build a roughly period replica endurance racer (so need to get lights in or on the fairing nose), tune the motor (maybe Wiseco 836, new cam, CR carbs etc), oil cooler, clip-ons, rear-sets and so on. Everything that isn't right will be reworked, repaired or replaced. No urgency but I'll keep posting in here and asking questions of the great and good as I go along.
Cheers