Sorry for posting twice in succession...
A bit of random rummaging through some old ABCs turned up the following:
PA1 routing varied season to season and also day to day.
In Summer 76 it flew
SFO – TYO – HKG – BKK – DEL or KHI – THR – FRA – LON – NYC – SFO and depending on the day called at IST as well (but terminated at NYC)
In Summer 69 it flew:
LAX – HNL – TYO – HKG – BKK – [RGN] – CCU or DEL – KHI or THR – BEY – IST – FRA – LON – NYC - LAX
Also S69, BA537 flew MAN – PIK – NYC – ANU – BGI – POS – GRG
They also had a 9-sector flight to Australia:
BA720 LON – ZRH – BEY – KHI – CCU – KUL – SIN – DRW – BNE – SYD
Also in S69 Channel Airways CW02 is shown as originating SEN and calling at Luton, not Stansted, otherwise as detailed by thegoaf.