FYI-throwing knowledge out there for whoever might need some
I removed the REAR 56 leafs/brackets off the 1008 today and took the following measurements:
Front spring eye to center pin=26"
Rear spring eye to center pin= 29 5/8th
Confirms there is an offset
Bracket (front of rear spring (center of hole)) to center bumpstop=25 5/8th
Bracket (rear of rear spring (center of hole)) to center bumpstop=30"
Remember the rear has the shackle between the bracket and spring. Its 4" center of holes (6" overall).