It's an old post but for future reference I recently fixed this problem.
It was the fuel injector. I replaced it since all other things failed and that cured it. The old one wasn't leaking and just by looking at it the spray pattern looks the same to me. Never really tested the injector itself.
It cranks twice as long now (weird) but never floods. Starts first time and runs, no stalling.
[This message has been edited by cebix (edited 06-14-2020).]