Stuart - an analogy would be a distance runner trying to run a marathon in a coat and tie, with the tie cinched up about 2 inches too tight!

The engine will labor, and run hot. Over some period of time the hot running will eventually kit the engine.
Brendan - the "fleet" carbs are extremely rare; but unless you plan to open a carburetor museum or are doing a numbers matching restoration on a taxi, best left alone. In 37 years of selling carbs, I can count the INQUIRIES for fleet carbs on the toes of my left hand!

We have sold one rebuilding kit for a fleet carb about 10 years ago.
Most of the fleet carbs were painted a different color (most were brown or gray) so they would not be used inadvertantly.
Maybe another use would be a 6x1 set-up! :crazy:
Jon.