Thank You!!
I looked at the Sim file again, that joint is at 48" It is glued. The last place you want to cut it is there!! You don't want to cut thru the coupler because then another standard coupler to rejoin it together will not work. The best place to cut would be at 60 inches from the aft end. That will allow for a new 12 in. coupler to fit up to the old one (aft) and 6 in. into the top part of the booster tube. Then you are talking a 61 in. or so long box for shipping.