Does anybody know what size carb I should get for my Blaster?

I was thinking a 34mm Mikuni round slide carb for 100 smackers. With a clamp on K&N w/outerwear and aftermarket intake manifold w/boost( 130 smackers).

I baught a 1/2 inch reed spacer and might buy new FMF torque reeds or Boysen Reeds from Vitos Performance.

Is a 34mm carb to big for a stock cylinder? Will it get to much air&fuel?

Whats that big box on top of the stock carb? Is it a T.O.R.S.?