alright, mine was way too small too.
like could NOT get the knife in, heres some good advice. (mine fits just how I want it to now)
take th sheath, remove the metal (idk what you have to remove the metal actually, but j33ps said to, I think its so the holes don't deform or expand if you get the kydex in that area soft)
take a hiar dryer or heat gun (on low) and heat the area you want to get soft until it gets a little soft (not too soft) then put the knife in and mold it how you want it, and maybe pull the knife in and out a few times.

pretty much heat it and make it how you want it, I tightened mine in the blade more and lossened it near the handle.
its whatever you want, just don't go overboard.
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