How long, how long?

Latest progress report:
The back wheel is pretty much finished other than polishing up and bolting back together.
The Disc is not the one off the old chassis but sourced off an Aprilia RS50, i have a caliper and master cylinder to go with it too.

The frame loop is finally happening too, the tubes that make up the back half of the loop have all been tacked into place and the temporary bracing removed.
I made a bit of a discovery when trying to fit the spare engine cases, as in - it wouldn't fit.
After removing the bottom engine mounts it has gone in but it's really tight, and it just means more work fabricating a new mount. What the frame is off I've no idea, a GSX750 maybe, it looks the same but is just different in the detail. Even the headstock is a different size as i fitted the forks to set up ride height and ground clearance only to find the bearings are totally different sizes and the main tube too long.
On the good side it looks like the 6 degrees of rake we added was just right. The forks can now be dropped right through the yokes until there is only 2" of travel and the ground clearance is spot on. So i went ahead and fitted the barrels, head and importantly the headers. And as if i had planned it, there is still enough clearance for the front wheel. Magic.
Next on the agenda is setting up the back wheel position and deciding how much longer to make the back end, one influence here is Sams van. There is only 4 inches spare any longer and it would have to go in diagonally. So it looks like a 68-70" wheelbase it is.