What A/F ratio you running?

So I recently installed a wideband O2 setup on my small block street/strip setup. I followed the instructions on the placement of the O2 sensor (in the 3" collector angled downward). I know ideal A/F is 14.7. I have tuned my new Holley HP DP carb and idle is about 13ish and cruising is about the same, still haven't checked it at WOT. I'm kind of scared to run it any leaner (Just in case). I have already went from 69 jets in the primariesdown to 65 jets and adjusted the idle mixture screws on all 4 corners. Im running 91 octane ethanol free. Should I leave it as is or try and lean it out more?
Motor is a 10.5-1 360, 904 trans, kb107's, ported J heads 2.02 valves, Howard's street/strip cam around .550 lift, headers, 3" exhaust ( I know too big, but it's what I had already). With the Hughes 4k converter and 3.91 gears the car is no slouch. Thanks for the insight.