The deal with the Israelis, I believe, was that they could make simple modifications to thier aircraft that would take mountains of paper work and red tape to accomplish in the US.
I seem to remember one of the Mods was a simple Mirror somewhere in the cockpit that gave them some advantage.
But I think what I am talkign about was 10+ years ago easy.
You're right. It was rear-view mirrors mounted on each side of the cockpit bubble on their F-16s. Simple and effective.
That mod was a mirror mounted on the outside of the canopy bow so they could see what was going on behind them. The USAF adopted the idea, but in reality it didn't work. The mirror vibrated too much to allow any idea of what was happening.
Many of the Israeli mods look better on paper than in reality.