Defrost time black wire -where to attach

I have a new defrost timer coming early next week, and from pre-reading the instructions and watching the video I need help to know which terminal to put the black timer wire.

The unit has been warm (50-55 degrees) several times, and when adjusting the thermostat I heard a grinding/rubbing for a bit, and then it stopped. I tapped the housing that covers the defrost time and thermostat and heard the grinding again. I did this a few times until it didn’t seem to run anymore and the compressor then came on in a little while and cooled the unit for a few days. I’m hoping this cures the problem. I have also ordered a replacement thermostat just in case it needs replacing too.

Thanks,

Miketn

See the attachment for the wiring diagram.
It will help you decide how the timer is installed.