I haven't posted on here in forever but my Dad bought a really clean 2001 Cherokee with a blown up 4.0. I've got a 97 head I want to use to get away from the cracked head issues the 01s seem to have, which is where it gets complicated. The Jeep has 4 o2 sensors and 2 "pre-cats" that are part of the manifold/down pipe, none of which will work on the older head. Can I buy a steel header and weld in 2 bungs near the collector for the pre cat o2s and move the two post 02s behind the cat that's beside the transmission? Or could I adapt some sort of o2 "simulator" made for a mustang etc.. and just get rid of the post cat 02s? He's retiring soon and needs this thing to be no bs and reliable. I feel stupid asking this but all my research leads to be jeep forums and a bunch of flame wars over "illegally" removing catalytic converters. We don't have emissions or inspections here, I just need it to run right with no check engine light on.