Thermoquad vs holley vs q-jets

No drilling the rear blades is not the best way, nor was the PCV port in the rear of the baseplate the best place. Your either placing raw air or in the case of the pcv raw oil vapors into the cylinders. Put it up front where it has a chance to mix with the fuel. And if you drill the blades too large, which often happens trying to get the right tune, now you have a choice. Close up the primaries and lose transfer slot exposure or throw away your rear throttle blades.