the oil orface was already removed because the block has already had a VTEC head on it. Y8 I believe. I have the Z6 bolts. But been using the A6 headgasket. could this mess up my head??

When I first put this block in, I put a Y8 head on it and it was making a crazy knocking noise. I reset the valves and that helped a little, but it still made a knocking noise. I replaced the bent valve in my Z6 head (had the cam checked and it's ok.) put it on, and after a few seconds it made a different, new knocking noise. I checked the bottom end and it's fine. I'm just super confused on this.

As for the thermo sensor, I could I just used the water tube/thermo housing off my Z6 block on the A6 block, right?? And let the other sensor just chill. I did that before and it worked. I just FORGOT that I had to do that before I dropped the motor in.