I have 6 of the titled used shafts, no head, no grip and would like to use for a customer as a Senior flex (on a limited budget). They say R flex on shaft. I have included current specs of shafts. I don’t think there will be a 5 iron in the set. Will installing a 6 iron on the 5 iron shaft equal an “A” flex. Or should I buy 1 additional shaft to use on the 6 iron and then use the 5 iron shaft on the 7 iron and continue with the rest of the set. Hope this information is helpful.