HX to EX? O2 sensor Q's?

ok, I got a 96 HX, now since its already vtec, the wiring should be all there im assuming. so I want to bolt on the Y8 head for the performance oriented vtec instead of economy oriented. anyways, Im guessing(hoping) the oil passage for the vtec pressure and whatnot is the same and the only difference is the cam/followers's in the heads themselves so this is possible. I will use an OBD2 civic EX ECU, only concern I really have is the O2 sensors, I dont know where/how many the EX has, Im guessing 2, one before the cat, one after. but not sure, also Im guessing the EX doesnt have a mani/cat like the HX does, as I want to use a header for an EX as well. there is no smog here so I dont need a cat. I have the means to modify my exhaust to work with whatever manifold/header I use. is there a way to trick an ECU into thinking the O2 is there and working, make the ECU not look for it, or should I just weld in a couple nuts to the header and drill a couple holes and thread in the O2 sensors like they were on the stock manifold, just now it has no cat....

also what kind of cr is the HX?, the EX?, bore/stroke are identical correct?

I know this wont be a huge power gain but its soemthing to do, something to say is done, and will at least move me around a little quicker. plus I cant find a header for the HX.

I also have a quick Q about the ECU's, when does the vtec crossover in the vtec-E ecu thats in my car now? will the HX intake mani bolt to the EX head (I assume so but wanna be sure) and if the crossover points in the ECU's are similar, the fuel/ignition maps would still be far different right? it would just be kinda cool to keep the shift light, not sure why cuz it bugs me sometimes but I like keeping everything that works, working. and im sure the EX ECU doesnt control the shift light, or is that a seperate smaller ECM for that light?


*edit: I looked on ebay and no Y8 heads right now, but some Z6's. if I use the OBD2 sensors on my current setup for this head, will it still bolt up and function correctly?