After market rockers are short on top + don't connect at the vertical pinch weld.
The inner rocker panels are sandwiched into the outer rocker + inner floor assembly. along with the connection of the Center pillar creating clearance issues.
What I've found are few KJ's with perfect rockers . . . Cut the donor section parallel to the rockers in about 12" in, the posts up 12" or so , and splice the assembly onto your Jeep.
Cheaper + faster than disassembly, cutting rot + refabricating adjoining rotted metal.
There are few if any OEM rockers + inners available . nice path, but the outer were over $700 when still available. .... and the end caps are long out of production.