Once you remove the flywheel retaining bolt that screws into the end of the crank (easiest using a rattle gun), you will see there is a thread cut into the inside of the flywheel. As you screw the tool into this thread it will eventually contact the end of the crank and in turn will force the flywheel off as you continue screwing in the tool.
Using the swingarm/axle bolt performs the same function if your lucky enough that it is the same thread.
As the XL has a large external rotor type flywheel, another option is to gently tap around the outside of the flywheel with a soft hammer. This will work well enough half the time but be warned if you hit the flywheel too hard you will do irrepairable damage so softly softly tap, don't belt it & if it doesn't come free after a few taps, get a puller. I actually did this on a XL250KO last nite, gave it one very lite tap and the flywheel fell off
Jap bikes generrally don't use jaw type pullers to remove anything, all the ones I've seen screw into the flywheel in one way or another