Perhaps you can provide some enlightenment on this topic (or maybe not, considering a NDA) - but my understanding was that parts were scrounged during prototyping while the internally designed system was still being developed (like Toyota with the Prius, it took awhile at Ford to get the thing to even start properly...) but that those were place to allow testing and prototyping, but replaced for production models. I could be wrong - but I've seen absolutely freakish blends of different vehicles slapped together just to get prototypes out on the road for testing of components.
From fastcompany.com's article (From: Issue 87 | October 2004 | Page 106 | By: Chuck Salter):
"Ford could have done things more simply. It might, for example, have bought part of Toyota's hybrid system, as Nissan has done. But in November 2002, less than two years from the scheduled start of production, Martens decided to develop the technology in-house. The only Toyota patents that it licensed, he says, were to avoid patent infringement. "That was a defining moment," he says. "It took away the safety net.""