[DuSpinnst]

Change Saturn into Opel, re-brand the stores and the cars. Don't change the dealer network. Take the smaller Saab network, buy out the dealers and combine Saab with the "new" Opel dealers (Canada already does this). There you have your "European Channel."

Take BPG, and par down the model line. No shared platforms between them, that means if Buick gets an Epsilon Pontiac doesn't.

Then make Cadillac and Chevy individual channels, and dump Hummer. If you MUST keep Hummer par it down to two models (H3 and H4) and sell them next to Pontiac Buick GMC, also that would mean you'd kill the small pickup/SUV of GMC.

That way you'd have 4 healthy sales channels.

Chevy - Volume
Pontiac/Buick/GMC/Hummer - People who don't want a Chevy
Opel/Saab - European Imports
Cadillac - Luxury