And if you don't have a pin, just put a scrap screw in one hole and turn the
winch against it. That's what I do.
Some of the tools
sold for opening filler caps (the ones with lots of options for "blades" and double "pins") may have pins at the correct spacing. If you have one on the
boat, give it a try. It could bend though, depending on the material and the amount of resistance the threads of the winch cap give you. It sounds difficult, but it's super simple to open one up.