READING 70 SWINGER 340 SPARK PLUGS
What brand plug is it?
If it's a Champion, it's about two ranges too hot, rich at a cruise and most likely at WOT. It needs more timing, or a quicker timing curve.
If it's an NGK, it's about 1 range too hot and the rest is the same.
If it's an Autolite, I'd be guessing.
I'd still like some better pictures.