Holley 670 SA tuning with wideband

How much rich on the cruise does it go?

One thing I found with basically the same setup (Edlebrock carb though) is that you can get somewhat leaner on the idle mixture than 14.7 without a lot of complaining from the engine.
This will bring down the cruise A/F a little leaner.
You wouldn't however want to try to get away with that at WOT due to leaner mixtures causing more heat.

Another important detail that probably wont apply to you because your WOT was already withing range is that when you go leaner you have to be a bit carefull of preignition (leaner makes it happen easier)

One thing that may or may not be related to your specific location is that I frequently drive down to Phoenix where the elevation in 2,000+ feet lower, so I left my cruise mixture a hair rich (like around 13.5 - 14 to one) so it doesn't tend to run too lean and get hot easier because of it.
This time of year it gets in the 106-112 range down there.

Just thoughts.