Checking.........
Only Canadian bulletins I see remotely in the correct time frame are #1276 dated 65/09/24 Antenna installation for '66 B body cars with factory radio and factory a/c; 1285 dated 65/10/29 same thing for just Plymouth B-body cars; 1285A dated 66/02/04 Radio antenna mounting template, all 1966 pass cars; 979 dated 62/02/20 Antenna trimmer adjustment for Cdn built cars. There are none from anything like the 1965 model year.
In the 1965 Chrysler Plymouth TSBs (U.S.) I found 65-50 dated 65/02/24 Manual antenna installation and radio trimmer adjustment, 1965 CYP which is the only one.
The bulletin I've already mentioned is the only one with "antenna" in the subject line from the 1965 Dodge U.S. TSBs.