As you can see, the fibreglass tailpiece I have is the same as the Jota's.
I've been in email contact with him ( Initially he was Grant Saunders, but now goes by Jacob) and he thinks he only did 3 frames. I sent him a photo of my frame number ( which has a 7 on the end) and he said he definitely didn't do 7. Which was odd.
The swingarm was damaged - looks like the chain jumped the sprocket, and got jammed between sprocket and arm and bent / dented it and cracked the braze.
I had made a list of what I wanted from a donor bike, and picked one up - the Triumph Daytona 900 would give me good wheels for modern rubber, discs, 4 pot Nissans, multi adjustable forks, yokes would fit and swingarm was the right width ( so no issues making up spacers ) and the Saunders swingarm pivot bolt was the same diameter as the Triumph one. But the Saunders swingarm mounts its shock like an LC350 so I needed to get a mounting made - I chopped a GSX-R 750 K3 up to get its brace and a local fit that does race bike stuff welded it up for me. I'll try and add a photo.
The Triumph engine wouldn't fit ( clutch cover sticks out too much) so I sold all the Triumph stuff I didn't need and started looking for an engine/ carbs/ loom/ electrics etc .