Two examples:
Lionel 8753 GG1 Tuscan 5 Stripe C-7
Lionel 18313 GG1 Green Single Stripe TMCC (C-9 Display)
and/or
Lionel 8150 GG1 Green 5 Stripe (C-9 Display)
Lionel 18314 GG1 Green 5 Stripe TMCC (C-9 Display) LCC-DC
So that the TMCC locomotive controls itself, and the double headed non-TMCC locomotive.
Guessing some interconnect cable is needed ...
THANK YOU