Thanks All
Being a CAD Luddite I've gone for the TAP method.
Tape And Pictures.
Looking through the rear hoop facing forwards:
Looking from above the front wheel tub facing backwards:
Side view:
Another side view:
The tape represents 1.25" DOM tubing, the two longer ones from the top of the upright at the back of the wheeltub down to the bottom rail at the hoop they comes down from the front hoop then back up to midrail height on the back roll hoop will be rolled to follow the body contour, the rest are straight.
The whole roll hoop structure from the midrail up and the feet area (the non crossed square next to the wheeltub) will be plated on the outside using 2.4mm (0.94") FMS.
The rest of the riders compartment will be skinned with 1.6mm (0.63") sheet.
The lower control arm mounting points will tied into the the bottom rail, the wheeltub and the upright rail at rear of the wheeltub, the control arm will be boxed out of the riders compartment.
Going to submit to the Motorcycle Tech Committee now.
Regards
jon