Hi,
While I can only provide some general information and not something specifically tailored for golf, I believe the same principles apply here.
Okay, so: to retract the brake piston, you generally have to push it in and turn it *simultaneously*. I usually use a regular C-clamp to push it in (placed across the entire brake cylinder, with the clamping part pressing on the piston). Then, the best tool for turning depends on the surface of the piston; if the surface has holes or grooves, you can use an adjustable wrench or a large screwdriver to turn it. If nothing else works, you can also use a large pipe wrench, but be careful not to damage the rubber boot. After you've turned it a bit, you need to tighten the C-clamp again... and so on. etc.
It's not as complicated as I've described it here

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Regards,
Private.