I did the exact same thing about ten years ago. I bought three Rochesters still in the boxes - never used. I rebuilt two of them with kits and have been using them ever since and I have been happy with them. I will tell you that I pulled the chokes off of them and rebuilt them as "basic" carbs using a cable choke and cable throttle, although this may not be necessary.
On the rebuild, I also lowered the float level to between 1/8" and 3/16" lower than called for in the rebuild instructions. I felt with the lower float setting in the bowl lower, I would have a better chance of not having any leaking problems where the top and bottom of the bowl goes together. It has worked fine. If you were using a single carb, this probably wouldn't have worked, but with two carbs, I think there is enough fuel in the bowls to handle a lower level. I have never noticed any lack of fuel being a problem, even under a hard acceleration.
The best part of the whole thing is that my engine still looks "period correct" because it has the right looking carbs on it.
