For a stock street build I don’t think balancing will be a real issue. Just get the correct front dampening for forged crank and remove the counterweights from torque converter or get a new one without counterweights.

A friend of mine already made it and he used Kb240 pistons instead the stock ones. Everything came out fine without really take the rotation assembly to the shop for balance. So far so good he haven’t noticed any kind of issue and has being driven the car for 2 or 3 years now. I was to make the same but then decided to stroke my 400