Help needed, tail light wiring harness- 53 Victoria

[53vicki]

53 Victoria. Car does not have back up lights. Tail lights come on with headlights but car has no brake lights.

Here's what it looks like at the tail light housings-
Drivers side tail light harness has;
- wire with single female bullet connector
- wire with double female connector
- thick white wire that has been cut, not connected to anything now.

2 Wires from Drivers side tail light housing are connected to -
Green is connected to the single female bullet connector
Black is connected to one of the openings in the double female connector, other opening has no wire going into it.

Passenger side harness is same as drivers except it does not have the thick white wire that the drivers side harness has.

I don't see any grounds on either tail light housing. Do I need to plug a wire into the 2nd opening on the double bullet connector then ground it ? Also where is the thick white wire on the drivers side harness supposed to connect ?

Many thanks, trying to get this vicky roadworthy so my Dad can finally put some miles on it before our short driving season here in MI ends.