Polar crossings were certainly not common in the 60's as they simply did not make any sense from a flight planning point of view. I would be very suspect of anyone claiming that they they did polar crossings or even operations above 78 degrees. Yes, we did grid above 72 degrees as I recall?
Regarding the 707 Nav station which was in the aft left side of the flight deck you might recall the sighting stool which the Nav could stand on so as to get a better angle on the sextant eye piece. It normally stowed against the left aft wall. Also there was a drop down curtain to prevent light from the nav station expanding forward flight deck.
I spent about eighteen months as a 2nd Officer at Pan Am before the Bendix dual doppler and Edo Loran A took over and slowly displaced the Nav positions.
Good times for sure
