If my other diagnosis do not work I will be heading down this route.I would buy oem O2 sensors and relocate them to the manifold. That sorted out rough running and codes in my wife’s 94.
Leave the current bungs in place and pull the connectors into the engine bay. Wrap the wiring in heat/fire proof wrap, install the new oem sensors.
The relocation requires delete of the PAIR system. So, if you have yearly smog, this probably won’t work for you.