"The essential philosopher"

Greetings, Foucauldians. Long time no see. :)

My travels these days are taking me deeper into the Heideggerian woods. I
often think of Foucault's comment in that late interview: "Heidegger is,
for me, the essential philosopher." The thought struck me a while ago that
Foucault's and Heidegger's lives--if not their careers--overlapped a good
deal, and that Foucault conceivably could have met Heidegger. Does anyone
here know if such an encounter ever occurred, or if not, whether Foucault
ever expressed any feelings about the prospect of such a meeting?

Also, does anyone know if Foucault ever elaborated anywhere on what
Heidegger meant to him--which of Heidegger's texts he was familiar with
and influenced his own thinking, and how he thought of Heidegger vis a
vis his often-stated antipathy toward phenomenology?

Matthew