tufcj
You can, I've seen it done. I've also seen re-drilled leaves fail miserably. You create a weak point both at the new hole, and at the old one. Leaves can crack if they flex at either hole. The original holes are drilled before the springs are tempered, so they're fairly solid when clamped down. You create a stress point with the new hole, and at the old open hole. You'll need a cobalt or carbide drill bit to drill the spring steel, anything else will quickly dull to the point of not cutting.
Can you afford to have one fail on the trail?
I've seen guys make a plate that centers on the old pin, then has another pin welded where they want the axle to sit. Or if it's just an inch or so, redrill the axle pad and the u-bolt plate the same amount off center. I did that to move the axle on my CJ forward when I had the WP shackle reversal on it.
Bob
tufcj
