1998 Chevy Blazer replaced head gaskets and having issues.

I have a 98 s-10 blazer.
I had been loosing coolant internally, but not smoking. I noticed steam around the radiator, but found that it was coming through the intake. The filter was wet and the air box had water in it. I assumed the intake gasket was bad but my dad said possibly the head gaskets. So I replaced them both. It took awhile. LOL. Stabbing the distibutor wasnt easy, but I finnally relized you had to stab it half way between 1 and 6. Thats not in the haynes manual. LOL. So now the engine runs but it doens have a lot of power. It had a little steam, but once warm it went away, however their was some water that came out the exhaust. But no sign of antifreeze in it. Maybe residual from the bad head gaskets before? Anyway now it has a knock in the valve train. I adjusted the valve/rockers per haynes. I did notice that after the balancer and timing mark were lined up the #1 still traveled up a little before rotating down the cylinder. Should I have adjusted them at that highest point or at the tdc by the timing mark? I'm very frustrated. Any suggestions? Also the service engine soon light is on. I guesse I could get a key from autozone and check that out. However, it was running great upon initial start up. Then the light came on, then the exhaust fluid, then the knocking/tapping in valvetrain. Thanks, T.J.