Found this photo, which must be mid/late-1970s judging by the mix of BEA/BA schemes:
Visible (just) are the Alpha stands (abeam the taxying aircraft), with A1 having disappeared under the Shuttle gateroom, A3 with a Trident parked at an angle, what looks like a pocket DC-9 on A5, and A7 empty.
Doesn't look like there was an A9, so 4 stands on the Alpha side and 5 on the Bravo side of Pier 4.