Heavy mouth breather here. When I overhauled my 261 I wanted to see if I could get a little more out of it also. I went to Tom Langdon and he set me up with a Bulldog cam and a Nicson manifold and dual 32/36 Webers. It took some tinkering to get it synchronized (I enjoy tinkering ). Now when I'm running down the road and I put the pedal to the metal and those secondaries open up it's like that 261 goes into another gear. I really enjoy driving the old stovebolt around and that little extra power makes it even that much more enjoyable. No regrets here. Good luck with your project.