The American fuel from Ascension Island was actually a small amount. Gratefully received, but the Task Force didnt rely on it. There seems to be a myth that the TF relied on fuel from the island.
You are correct to state that the UK also got some of its intel from America.
In 1956 the USAF reopened the RAF Ascension Island airfield, now called Wideawake Airfield USA and have continued to operate it since. The runway was lengthened and widened in the mid 1960s to allow for larger aircraft.
USAF and NASA have a missile tracking facility at Cat Hill.
In 1982, the RAF re-garrisoned the airbase as a staging base for the Falklands War. Operation Black Buck, the long range bombing raids, were carried out from there.
Every hangar, drop of fuel from the tank farm, bunk bed and coffee pot was initially provided to the RAF courtesy of the USAF.
Of course the RAF resupplied later, but the USAF laid the red carpet for the initial Falklands campaign. We did much of the air to air refueling for Vulcan bombers of Black Buck as the Victor refuelers were in short supply. We air refueled the Victor refuelers that went on to the Falklands.