If you want a deal on new carbs, Jason Busat from BadAss powersports sells new carbs with intake manifolds and fuel pump for $1250. I got a set from him and they are new. He strips these parts off new engines and puts fuel injection on the engines. Here is the stuff I got from him a couple of months ago. JImChuk
PS a pair of floats should not weigh more then 7 grams together. I've seen them weigh as low as 2.8 grams each. I would verify this is not the problem. Also, do you have a return line? New style fuel pumps make more pressure than old style ones.