Per the drawing below, where's the best place to solder the ground wire?

wherever it's easiest has generally been my motto.

Good motto... I approve.

I'd try the slot...

I find the ground connection on plugs like that to be a huge pain in the ass. Do yourself a favor and roughen the surface where ever you do try to solder, Cardas uses some slippery f'ing plating.

I find the ground connection on plugs like that to be a huge pain in the ass. Do yourself a favor and roughen the surface where ever you do try to solder, Cardas uses some slippery f'ing plating.

I was wondering about that. Thanks for the advice.

Heck, thank you ***all*** for the advise.