mtech,
email Barbie or Jim, they have a little instruction sheet with the right drill sizes, and procedure to install their liners. Basically, its as follows.
Remove breechplug and make sure your new touchhole will not interfere with the breechplug.
Remove the old breechplug, and re drill with the appropriate size bit, for a 5/16" its a 9/32 or letter L bit.
Counter sink that hole slightly. Maybe 1/64?? I'm guessing. This will determine how thick the remaining wall is between the main charge and primer.
Tap the hole with the appropriate tap.
Install new liner till it bottoms out.
Cut off exterior of liner and file to the barrel flat.
Check the inside of the barrel, touch up any areas where the liner may have come through or burrs.
Reinstall breechplug. I usually open the touch hole slightly.
I won't use any thing but a White lightning.!!