Why the T%^# Would you want that? you could remove 2 big-ends and pistons, but that would defy the purpose of having a 550 right.
Nhee just joking.. Only thing i can come up with is machine the intakes so they will accomodate to cilinder ports, but only one carb. (T-shaped).
But again, why? You would need bigger carbs, needles, and a shitload of spare time, whilst the result will be nowhere as good as 4 carbs in 99% of the cases. If it would heve been better, Honda would have done it don't ya think?