Some of the early 767's did have an F/E..notably those operated by TAA.
Have a look at the link below and click on the before and after images.
767 Flight Engineer station | Jetcareers
The panel configuration also varies significantly depending on the operator, however, as a jump seat, it's very comfortable and you can happily spend many hours watching the two monkeys in front perform their onerous task of watching television screens..... and eating at the same time...the latter was not always a pretty sight.
As for F/E's, Air France, being Air France, also carried them on the Caravelle and the early 737's....quite why remains a mystery known only to AF however.