I agree with Hank, as they did use Q-jets on the 230 Pontiacs with no smog prior to 1968, also 250 motors into the smog era. I would find a pontiac ohc lovers site and look at the different jets/rod combo the factory used. The rod are also stamped near the top (bent end) like 41 for .041" dia. for the econo (cruise) position, the standard power position is like .026 dia and never stamped- the stamped number is always talking about the cruise position. An example- a'67 275hp/327 would use a .071 jet with a .044 rod. The pontiac 6 would be some different, either or both the rod or jet. The Doug Roe Rochester Carb is excellent for Q-jets- Read that and you will see there is no need for holleys etc. Folks malign Q-Jets 'cause they dont know 'em!
