Neutralize salts after shooting needs to leave un-neutralized it'll rust the bore and anyother opening (Nipple & Drum).
This model has barrel wedges that need to be removed (make shure they go back in same side they come out (on reassembling press them in by hand till no barrel movement) its possible the chamber may be stepped (powder is in a smaller diameter bore), then the barrel can be unhooked from the stock and removed, unscrew the nipple and pour some nice hot tap dish soap treated water down the bore and use a brass brush and run it in the bore a couple times to bust loose any crusts of old porpellant, then continue with a jag and patches till its clean useing plenty of hot soapy water, rinse clean when your satisfied its clear of salts you treat it like any other bore (Milsurp corrosive ammo) and oil the barrel inside and out it with oil saturated patch/cloth, I like to use 3 in 1 machine oil.
that's How I would do this particular barrel.
any threaded holes need to be cleaned too, check the Nipple and Barrel and see if the breechplug is forged part the barrel or threaded in the back end?
Some You-Tube Video for flavor.
http://youtu.be/VQT4CF2ab64 this fellow did a poor job and them guns is rusty
http://youtu.be/O3y_GyyMWMk the bathroom shower job
Cleaning a Traditional Style Muzzleloader - YouTube
this one is quiet and round about but good
http://youtu.be/AX7KyhSSow0 this guy is better but has diffrent model
http://youtu.be/B3WQqJPbUVw This Flint Lock fellow is really detail'd