I'm traveling thru Lincoln Neb. Thursday so I'm stopping off at Speedway to get the extended shafts for my 3 94's, I see a reference to a primary throttle plate and secondary throttle plates. Whats the difference between the two? The carbs are all identical 1 1/16. A little confused, but I'm teachable. Thanx, Gary

       

Gary, 55 Vicky, St. Germain, Wisconsin