Just put new NGK BP5ES in.
Clean fuels make diagnosis difficult sometimes. The correct area to check if it seems ok,
afaik, is way inside at the base of the porcelain.
fwiw.. there is a fine line between rich and nice as some popping may occur at idle with a hot muffler when "nice". These carbs are great but in a crude sort of way. It's not a Holley or a Rochester.