What scale do you build in?  Mini Exotics has a nice 1/24 transkit of the
Breadvan.  You'll need a Testors/Italeri 250 GTO donor kit, and a bit of
scratch-building on the interior, but it makes a nice replica.  You might
also try the GPMA group on Yahoo (Grand Prix Modelers Assoc) - they are a
great resource for reference material.

Hopefully it will be back to the Cavallino Classic in January, and I will
take a LOT of pictures!  ;-)