I just took a look at that model online so I would know what you are dealing with.
In my opinion the best thing to do is install an actual thumbstud. This is extremely easy and simple if you have the right tools (drill press, carbide drill bit).
The design of that knife lends itself well to this because of all the flat area at the top/sides of the blade.
Basically, all that is needed is to drill a hole, and then install the thumbstud (the kind where a screw passes through the hole in the blade, then screws into the threaded thumbstud. There are a variety of thumbstuds out there, I usually get mine from Knifekits.com (look under "Knife Making Parts").
I use thumbstuds that require a 2-56 size screw (a screw will generally be included with the stud). For a 2-56 screw, you want to drill a 3/32 hole. So what you need is a 3/32 carbide drill bit. Carbide bits are great and will easily drill through hardened steel.
Thumbstuds typically come with flathead screws with a V shaped head. Such screws require the hole to be chamfered (a V shaped opening, this requires another carbide bit). But if you get a button head screw, then you won't have to chamfer the hole. Knifekits.com also sells 2-56 button head screws of various sizes.
If you install such a thumbstud, it might be necessary to file or use a dremel with a narrow grinding attachment to grind out a small area in the handle/liner on the thumbstud side so that there will be room for the thumbstud when the knife is closed.