Is This an Indicator of Detonation?

If the chamber is black it’s burning oil. Simple as that.
Geometry on a Mopar shaft system is the valve job. You can correct for it but I’d suggest giving Mike at B3 a call and he can walk you through getting what he needs to fix it.
That busing is oilite bronze. Shatter it into pieces and push it out the bottom. I have a puller I made and it just grabs the bottom lip, and if it breaks, it grabs the bottom edge that’s left. But even having to break it up shouldn’t be more than an hour with a long punch or piece of steel rod.