The Mig-23 used in the 4477th in Tonopah were Mig-23MS a very much downgraded version of the Russian Mig-23M. No IRST, no R-23, RP-22SM Radar and only R-3S/R and R-60 missiles and very poor BFM perfomance.
The ML-MLA versions were much better, with a redesign of the airframe, reduced weight, less drag and better aerodynamics rated to 8.5G, better engine with more thrust/weight ratio and overall better maneuverability. Also the radar was improved, R-24 missiles added, better HUD and ECM resistance.
The best BFM Mig-23 was the Mig-23MLD of course, with improved AoA handling, vortex generators in the wings and pitot boom, better FCS, avionics and radar.
So a Mig-23MS cant BFM better than a F-111 but a MLA-MLD is a completly different thing.
Is like comparing the Mig-21F from 4477th with the last Mig-21Bis variants.