Science and Energy wrote:
When you say "they are not even all the way from front to back" do you mean the mating surface which is vertical or horizontal?
2 points come to mind, I'm sure you've seen them already:
They aren't 'flat/smooth', in that they have contours bent in for rigidity.
(I don't think this second point is relevant to the rockers, other than measuring/locating the 'new' rockers into position as you're building them into the underbody).
The distance between the unibody 'frame' and the rocker is different at the front of the rocker compared to the rear of the rocker.
I didn't realize how much the distance between the 'frame' and rocker changed until I was under there fabbing up sliders, and looking for attachment points.