Here's the exhaust I plan on using for now. I took the 997 manifolds and added pieces off a B6 S4. The rear pieces are the catalytic convertors off the Audi. I'm using the cats as mini mufflers. With them off it's very loud. With them on it's just loud. I'll experiment with them on and off. I figure that I'll already be getting dislikes from the way the car looks. Ugly and loud might get me kicked out from events. I'm guessing the exhaust system weighs 15-20 pounds and the cats add another 10. On to the cooling system for today.
As for the window frame. I'm definitely not putting a windshield back in it. I'm torn between cutting the frame off or keeping it. I do believe it adds some rigidity to the body but not enough to worry about. My biggest reason for keeping it is that I plan on jumping this thing and the rollover protecting might come in handy. That being said, I do think it would look cooler without it and will cut some weight. I'm still thinking about what I want to do. I'll be adding some reinforcement tubes for sure though.