The antenna plug goes into the back right hand side (as viewed from the driver's seat)
There is only one place it can possibly go when looking at the rear of the radio. If I remember correctly, I had to plug the cable in before lifting the radio up into the dash holes.
You also need the special dash speaker mount and the special radio bracket that bolts to the right hand rear side of the radio. The radio should not 'hang' from the dash mounts only.
I have x-tras of these brackets if anybody needs them. They are pretty hard to find.
I used to be indecisive. Now I'm not sure. I feel like I am diagonally parked in a parallel universe. 1968 400 convertible (Scarlet) 1976 T/A - 455 LE (No Burt) 1976 T/A New baby, starting full restoration. 1968 350 - 4 speed 'vert - 400 clone (the Beast!) 1968 350 convertible - Wife's car now- 400 clone (Aleutian Blue) (Blue Angel) 2008 Durango - DD 2008 GXP - New one from NH is AWESOME! 2017 Durango Citadel - Modern is nice! HEMI is amazing! 1998 Silverado Z71 - Father-daughter project 1968 400 coupe - R/A clone (Blue Pearl) (sold) 1967 326 convertible - Sold 1980 T/A SE Bandit - Sold