1RedBoard

Hey all. Long-time lurker, first-time poster.

I have a stock (to my knowledge) 1998 XJ Automatic 4.0L with ~225,000 miles.

Awhile back I got stuck in traffic and it overheated. Ended up blowing the radiator and getting towed home. We replaced the radiator, upper/lower hoses, belt, water pump, thermostat, and electrical fan. Checked the head for warps and replaced the head gasket, valve cover gasket, and exhaust manifold gasket. It started right up, but was immediately pretty rough running. OBD2 scan has misfires on cylinders 1 and 2, as well as random misfires. Since then have replaced MAP sensor, CPS, TPS sensor, cleaned the throttle body, new O2 sensors (both), new plugs, wires, cap, rotor, ignition coil. Also just for fun, I installed 4-hole injectors. No change in symptoms or codes thrown. Still rough running and misfiring. MPG before the incident was ~20 on a good day, now I'm lucky to get 12-13.

What else can I try? I've gone through the wiring as much as i could without completely unwrapping, and checked all the grounds.