KBS tend to run 2 SW points lighter so changing to PX you may be fine with out tip weights. Having your clubs 1/2" over adds 3 SW points 

I better way to swing weight your irons is no tip weights and apply lead tape not the head where you want it. You need a swing weight scale. If a club builder is changing them for you , they will have all the stuff you need. When I reshaft  clubs I get rid of  the tip weights and add lead tape as needed low in the back of the club

. For all the claims of each manufacturer that each generation of iron heads has increased MOI by redistributing weight in club head, tip weighting seems counterproductive to me. Ideally each head should have been selected to a specific gram weight to produce the desired swing weight taking into account final build length and shaft weight. This is not practical when mass producing clubs so most manufacturers have weight in the badges applied to the back of the club or use tip weights. 

I recently pulled apart a  tour players set of forged muscle back blades. All heads had been selected for the exact gram weight that corresponded to the desired swing weight and were all exactly 7 grams apart in weight. He would rather apply weight with tape to change things. Adding to the toe ,heel or center to affect ball flight that he wants. I wish I had that much control !