Everyone seems to be going with the 3.55's. I'd put some headers and exhaust on the car before you did gears. It will liven up the car a bit. That and possibly some T&D rockers.
I personally wouldn't want gears in my viper as it is tough already to hook up in the lower gears on the streets around here. And I like the nice long hard pulls of the car, it gets you to that magical 150 number fairly quickly that way. :thumb: