Got the correct measurements - Thanks, Chris!
In the Premier instructions, they include this diagram:
All rods are P300. The measurements for the sticks are:
Spine rod: top and bottom are 29" not including the ferrules; middle is 28".
Spreader rod: top and bottom are 28"; middle is 14 1/2" not including the ferrules at each end.
Ferrules are 4" long.