63” swap

So i posted the other day and didn’t get any replies or hits on the post , guess i should’ve been more elaborate with my topic lol. I got a set of 63” springs the other day for my square , i plan on swapping them in with the ff14b. now how i do the swap is where i’m at a stand still, i have the 4” ORD shackle flip for the rear hanger but the front hanger not sure which route i’m going to go with. as i mean use the stock one and move it forward or buy a aftermarket one and weld to my frame. guessing off the differences each hanger will need to move forward 3.5” to keep the axle in the same place going from the 56” spring to a 63” spring. if anyone else has done this or knows what to do if i’m going about it wrong or any help would greatly be appreciated. this is of the many things i am taking on with this truck so my brain is a pretzel with it right now haha.

You are on the right track. Just move the stock hanger forward to locate the axle where you want it. Locating the rear hanger is just going to be trial and error to get the shackle angle happy.

I'd trial fit the springs as just the main leaves, with the rear hangers simply clamped in place. Then cycle the rear suspension with a floor jack. Or a forklift if you have one. You can clamp the hanger in various spots to find the best location to achieve a good shackle angle.