6000, 7000 or 8000 rpm tach?

I don't even look at my tach. MSD shift light with changeable pill is what works for me.

Exactly.

You may use your tach to see what you are trapping at, or launch RPM or double check things, timing the car, etc but you can't beat a shift light for shifting. Not to mention its safer and more efficient because you never look away or down.