Hi Tom,
Like Dan just explained, the Sig Bearcat kit started out as a Berkeley kit. I have a disk with most if not all of the Berkeley kit plans. Evidently, it is too large to attach to this message.
I might be able to send you that pdf on a thumb drive if you are interested.
I am pretty sure you would be able to build a model from these plans. The fuselage formers are shown, your should be able to reproduce the ribs, the fuselage is planked, the rest is fairly routine.
Keith