Hey Mate,
Not 100% sure on the power figures as i wasn;t after power just a proper tune.
Compared to the single webber i can say the power comes in from very low revs with no hesitation and pulls hard up to 5k.
They sound awesome too.
For the heater, as per the pic above, you are just taking the coolant from the block under cylinder 4 as opposed to taking it from the cylinder head. Heater works great.
I read a thread somewhere that this setup promotes better flow.
Have you got a pump yet? I have one from a CBR 900 if you need one.
Cheers,
Matt