There are many different carbs that may be used successfully.

Your choice should depend on, in order:

(1) The amount and scope of engine modifications
(2) Your expertise with the carburetors of your choice
(3) Your budget

These articles may help you:

http://www.thecarburetorshop.com/Dual1barrelcarbs.htm

http://www.thecarburetorshop.com/Triple1barrels.htm

Personally, if it were mine, I would use Zeniths from either a G.M.C. 228 or G.M.C. 248, depending on the scope of engine modifications. I like to make my changes appear as if they COULD have been factory; and the Zeniths were original on the G.M.C. A detriment from your standpoint to using the Zeniths is that they are probably the high end cost-wise to what is available.

Jon.

Good carburetion is fuelish hot air
The most expensive carburetor is the wrong one you attempt to modify.
If you truly believe "one size fits all," try walking a mile in your spouse's shoes!
The Carburetor Shop