Proper 8 1/4" Rear Brake Drum Adjustment Tool?

Okay, someone is going to say, "screwdriver". I tried that - it didn't work.

A slot screwdriver will adjust the drum brake tighter but will not loosen it. I can hold down the tension tab that fits into the adjustment wheel through the offset opening, but can't back the adjustment wheel up from the opening adjacent to the wheel. The screwdriver slips off.

I bought the only drum brake adjustment tool on the shelf at Auto Zone, and it doesn't work either. So instead of throwing money at trial land error, I thought I'd ask what works to back these drum brakes off.

Thanks in advance! :thankyou: