civiclxb16a

ok here is the deal I have an obd1 ECU in my obd2 civic. what I was wondering is it worth the work and the effort to get the sensors and add them to my B16 that it needs it only needs a couple of things the secondary o2 sensor is already wired and ready to go and I have a cat that has the secondary sensor hole on the way in. is there anything else I am going to need to hook up to pass emissions? (even tho I live in a state where all they do is look to see if you have a cat and if your pipes are legal) let me know. also in the back burner I was thinking about getting an ls block from a 2000 teg is that worth doing instead of spending the money on the sensor just do an lsvtec from an obd2 teg?