I have seen the original B767 sales brochures. The aircraft was marketed as a 3 man aircraft. Boeing went to 2 man, after Ansett had signed the order.Ansett was a very early customer if not the lead customer.
I think at least one Asian carrier (JAL??)operated the B767 as a 3 man aircraft as I remember seeing an F/E in NRT as part of a B767 crew.
The engineer was removed in early production aircraft when the A300-600 was certified. The mod to remove the F/Es station was not much as everthing was plug in. The F/E side facing panel had little on it and the F/E's duties were not complex.
In regards to the 2 man B727, a number of options were offered for the R/R conversion. As far as I know the only R/R conversions were by and for UPS and 1 executive aircraft that was for many years based in Oz but with a Bermuda rego. The UPS owned aircraft maintained their 3 man flight deck and about 100 B727 100s were converted by them. As a result they meet all the stage 3+ noise restrictions. Indeed the EEC 3+ noise standards were tailored around them.
I suspect that the OZ based aircraft did indeed have a 2 man cockpit. It definitely had an EFIS set up after the R/R conversion by UPS.
Interestingly the Fedex MD10 conversion has a 2 man cockpit
Wunwing