I was just about to suggest what you are about to propose. But you go for it.Do you own a lathe? if so, there is a fairly simple way to cut that keyway with an HSS tool bit. I'll share more if you are interested.
Not my post, but I'm interested.Do you own a mill or lathe? if so, there is a fairly simple way to cut that keyway with an HSS tool bit. I'll share more if you are interested.