First, take the kydex liner out. The screw at the bottom is what holds it in.
If it's too loose, which is how mine was for my BATAC, heat it with a hair dryer and slowly bend it a little more, and squeeze together to crimp it down a little bit. This will probably be slow going, and you'll have to try several times. Eventually you'll get it tight enough and then just put the sleeve back in, and you're done.
I like using the hairdryer because it didn't really heat the kydex up enough to melt it, even getting the dryer up close. The dryer actually shut off a couple times, but the kydex was still okay.
I did not tape the blade for this.
If it's too tight, here's what I did with a regular kydex sheath, so it should work the same way: I taped the blade, put the sheath in the oven at 250 degrees for a few minutes, took it out and tried inserting the blade. Didn't fit. So I repeated that several more times until I was able to get the blade in with moderate difficulty. Then I figured I was done, so I cooled the sheath, untaped the blade, and it fit very well.
