Spark plugs

Not nearly enough timing. You should have had 40-45 degrees of timing at the least at whatever RPM you used for break in.

Hopefully you didn't stick some exhaust valves.

An 8 sounds pretty cold unless you are up around 13:1 and with that ignition, you shouldn't see any fuel residue on the porcelain except for the fuel ring at the bottom where the porcelain meets the shell.
Checked valves during leak down test. 37 at 2300