I have a Customer who wanted the KBS Tour Steel Shafts put on his 2006 Callaway Big Bertha Irons 4-PW and have them at the standard D2 swing weight .Look like to me the best route would be to go with Tour Lock Pro Counter Plugs . I don’t know which
Gram or Grams weight to go with.
Britt, I used a KBS Tour with a Big bertha 7 iron. the Swing Weight I got was G-2. that was with the shaft cut to Golf works Info Sheet. Hope this helps.