I did some more research and reading and it seems clear that they adapted the TODD-AO 6 track format (L,CL,C,CR,R,S) to a 4.2 format (L,L-LFE,C,R-LFE,R,S) which they used for all thee OT films and the majority of 70mm films in the 80’s. Apocalypse Now was in a new format (L,LS/LFE,C,RS/LFE,R,S) where you could either have stereo surround or mono surround depending on your speaker configuration. What I found indicates they did not use that format for TESB or ROTJ, they stuck with the 4.2 mix. The ANH 1985 mix would also have been 4.0 matrix like the theatrical mixes. So the 1993 mix found in DE, Faces, and GOUT would have been the first 5.0 mix released followed in 1997 by the 5.0 Cinema DTS and 5.1 Dolby Digital for the SE.