I have a set of 3" lift shocks that I'm using to go leaf under axle for around a 3" drop on my cherokee.

I need to set the pinion angle, and i think I'm finally at the point where I need to do that. But I have questions.

1. Do I need the shim still? There's a triangle block just shy of 5" long, 1/2" high.
2. What's with the long flat piece?

Since the leaf springs are meant to go over the axle, and since I'm doing welding to get the axle right anyway, does this mean that I can take the center screw out and remove those two items from the leaf pack?

 

since you are welding on perches, you get to decide pinion angle. there is zero need for shims (those are on the wrong side anyways).

the straight leaf is an overload leaf, dont take that out. those look like MJ leaf packs.

 

They were sold to me as 3" lift XJ leafs. Skyjacker brand. Model jc25rsb...

 

they very well could be. just saying that MJ packs are usually 3 or 4 leaf with an overload. dont often see XJ packs like that. MJ packs wont even bolt in.

 

You don't need the shim.....clamp the springs together with a good c-clamp near the middle and remove the center pin...note which direction the head of the pin is (head up or head down).
Remove the shim
Now reinstall the center pin upside down from the way it was when you took it apart above to put it all back together

This is so the pin part of the centering pin is in the perch, and not the head of the center pin/bolt since you are using these springs upside down from the way they are intended.
You may have to cut it short some if the pin hits the axle tube before the u-bolts clamp it all together. - you should have some clearance between the end of the pin and the axle tube when the u-bolts are fully torqued (if not, how are you sure the pin isn't holding the spring up ??)