Where to start?

Thanks for the replys. I'm going to go up on the timing and see how that works. The miss was more noticeable when I went from 6.5 to a 4.5 power valve. That's why I think it's possibly a lean misfire also. The plugs are a little black and smutty which looks rich.
This is my first stroker, been out of playing with cars for 25 years. Things have changed a lot from my Mallory dual point and mild 340's.