Here's the tale... the 54 3100 has been on the farm since my dad bought it new. The 57 6400 same thing. I tried both carbs on the 54 and the 261 carb needed a freshening up. Soooo... I took them both apart, got my box of B parts and put all the best parts in the 54 carb. Then I installed all the crappy parts in the 261 carb and sent it to Florida for some R&R. After its vacation it came home good as new with all new parts. It was then when I had both side by side that I noticed one was larger than the other. I had sent the 261 to be rebuilt.
Going up the steep hill from the river bottom on SR 40 is a good 70 ft rise in elevation in 1/4 mile. At 55 the 54 carb stays at 55mph. The 261 carb will have me going 60 at the top.
Like my old buddy Vance said... "you ain't never got too much power."
By the way, Carl... I'm 71 and anyone who knows me and sees me doing 55/60 on these back roads would think something's wrong and I'm headed to the hospital! Oh yeah, don't worry, I still have the 261 from the junk 57 6400. May need it one day!