Converter for my combo

that damper seems like an odd size. the carb, 750-800dp. convertor, 8"-9 1/2". since it's a grudge nite hotrod put a nos cheater on it time at 2 seconds. you didn't mention exhaust, as big as your collector. i wouldn't recommend going and lower than the gears you have now but if you do change only go to a 4.10 as the cam will run out of steam with 4.5's or .8's