need some help???

I got a crv b20 that ill be plantin in my 89 si hatch. The harness for the ecu goes straight through the fire wall to the moter so all sensors are hooked up allready so i think at this point it would be easer not to mention cheaper to run the moter obd2. my questions are prety much to the point so here they are.1) I have herd by some one on another bord that i can not use the distributer that is on the crv block now ? is this true and if so why.2) when i got the moter the guys at the junk yard didn't get me the 2nd o2 sensor but however i scavanged one of another crv but it is the primary O2 sensor and i want to us it for a secondary o2 sensor will this work??? I will be running a 96-98 integra ls ecm and the moter is out of a 97 crv badged B20b4. These may be stupid questions and some may think it stupid for me to want to run this moter obd2 but i think it will be easer. one more question, dose the integra intake manifold have all the ports for the sensors on the crv intake man.? Any ansewers will be helpful, i just want to do my homework before i go to install this moter into my car to cut down problems and down time