Hi Simon,
I didn`t mean scale up the plans ie hull shape, I meant apply the building method, so if the mozzie plans say 4mm ply bulkheads at beams, then scale up material thickness proportionately, use 6mm. If Mozzie building regs say 20mm foam bulkheads at 200mm c/c, use 25mm foam bulkheads at 250mm c/c. you should then build hulls lighter than the old Tornado plans would allow, but have to make sure they comply with current rules. You would have to do this in conjunction with the Tornado plans so the hull shape is correct & within spec. Also need to make sure that all framing internals etc conform to class rules, as well as skin thickness & weight etc.
I merely suggested this as an option, since I`m not sure if building plans for plywood T`s are updated to be competitive with the newer production built T`s in terms of min. weight. Obviously need to stay within class rules if you`re going to all that effort of building a boat.

Cheers
Steve