Wanted to check back in on this.
I still have my new Edelbrock 650 AVS jetted .104/.116, using 75/37 rods. (way bigger jets than came stock!) I have slowly worked my way up to this, from very lean with my old 750 (covered in Part I) to this carb and the current setting.
As suggested, I replaced the NGK 8's with BPR5ES plugs. This moved the "blue line" down to the base of the electrode. (farther than the above photos show at this point) The hotter plugs may have helped some with the A/F ratios, but it appears to me that I need a step or two colder plug.
Timing: I moved it up to 34* (and previously had tried 36*) and I did a bunch of driving under all conditions, then today I moved it back to 32* and this motor just seems to wake up ...and pulls noticeably harder at 32*, is very responsive, better throttle response, and sounds happy. Did some open highway, some around town, a few WOT runs, went for a country drive.
So I am jetted stupid rich, and very low total timing, but it works. With the 10* bushing limiting my mechanical I am able to run 22* initial, and 32* total, all in at about 2500 rpm.
(I have my vacuum advance limited to 10* as well, but will see how this works.)
My idle A/F is now at about 14:1 which is good. Most of my other numbers are about 1 point richer than is usually recommended, but if I ignore that, the motor seems to run better. I did a lot of runs with WOT in the 12.5 range, but it felt down on power, and was on the edge of detonating. WOT is now 11.5 or so. My cruise is around 13. I am running a 518 (...John Cope built) and in OD at 2000 rpm it seems to settle in to a 13.5 or so.
Won't get me great mileage but no more detonation happening!! And the fuel ring base of the plug is now finally showing a nice brown color. (91 octane, no ethanol)
I live about 26 miles from Heartland Park in Topeka KS (NHRA Nationals there this weekend.)
They are open for test and tune on most Friday nights so I may get over there and see how it runs on the clocks.
Thanks for all the help. Love this forum!!!