[geezer#99]

That pic shows your balancer mark might be out of wack from where it should be.
The balancer could have slipped or the timing tab is in the wrong place.
The timing tab was at 12 or 2 o’clock position depending on motor or year. Timing cover could have been changed.
You need to confirm the balancer/tab are accurate.
A piston stop that screws into #1 plug hole works best.