Thanks fellas,
I'll email Damien from motobins and ask if he can put together a seal and gasket 'kit' for the G/S final drive as they don't have one listed and I'm finding it hard to figure out what is suitable.
Rucksta,
I'll happily grab a few shims. Any suggestions as to which ones

I'd prefer a wild guess from you to a stab in the dark from me

motobins list the crown wheel inner spacer shims from 1.6mm ranging to 2.6mm
and the crown wheel outer large shim from .18mm ranging to .88mm.
I think this order is just about ready to go through. I'm fooling myself if I think I will manage to get everything I will need in the first order anyway.