dbane261,
The engine will run reasonably well with any of the setups described in the posts above, in my opinion. I forget, do you have an automatic or manual transmission?I have run a couple of 261s with three "non-progressive" Stromberg 48s on the street with no problems (other than an idle speed of 800 rpm) and five "non-progressive" 48s on a 278 set up for off-street. I have no direct experience with Holley-Webers. If each carb has the "progressive" second barrel, I would not be afraid of running all three, even on a 235. I also ran two in-unison BXOV-2s on a 235. Experimentation is the way to learn, as long as you are not violating any safety guidelines.
Good luck, in any event,
