It's already making @ 350 horsepower (12.8@3200 lbs), do you really want/need more for the street? I would put a 4.11:1 gear, you're just driving it around town anyway. Put some really good tires on it, and leave it alone.
I see the rear window stainless moldings on the roof, are they straight? I would like to purchase one piece which is missing on my car. Must be perfect, or near perfect.