What spark plugs?

I think they look pretty good ,other then the oil from a valve cover leak i think you have.
It's hard to read a plug sometimes when your getting close to a perfect tune,but when you get that close,you start jetting for the kind of weather that your running in ,or as a good rule to follow,just jet the car to run leaner in the heat.
When it starts to get colder in the fall ,bump your jets up for the fall air.
You can hear the differance in a motor thats to rich.
It will not rev-up as fast under throtle and will act lazy and run not as smooth in the upper rpm's.
The engine with to lean of a jet, will do the same kind of thing as far as reving slow ,but will just not pull any rpm but will sound pretty smooth.
You want to keep the motor as fast reving as possible under throtle.
When you start to get to rich it will start slowing down on how fast it rev's up when going threw the gears.
If you go to the track,your mph is a good indicator of horse power.