Does anyone have any articles or sites online that they can point us to comparing the internal chassis of the TT Cab vs. the coupe?

In trying to search info on when the new 997 TT Cab was due, I came across a thread on another website where several subscribers were commenting how simple it should be to create a TT cabriolet when they already had the C4S cabriolet?

I know I've read somewhere that the 996 TT Cab and the TT coupe's infrastructure or skeleton are completely different and that due to the cab's loss of structural rigidity from the lack of a top and still the incredible torque, they had to design a tubular frame that was twice as light, yet twice as strong?

Does anyone else out there have any of this info or am I mistaken?