A (short) friend told me she bought a ninja 250 over the CBR because she could just pick up a lowering kit and pop it in all in about an hour on the ninja. Now I see what she meant about the CBR. Good luck.
So, which one are you going with Rodney?
Seems like you have found a few ways to do it... let us know how it turns out!
You sure those are for a CBR250R? I only see dirt bikes listed.
Be very careful here, her being comfortable while stopped is so much less important than the suspension being happy while riding that it is almost immaterial. Dropping a bike at a light is embarassing, grounding a hard part and crashing in a corner can have much worse consequences. Make the changes to the seat/boots/experience, not the suspension.
Rodney - Just remember that you also need to adjust the front of the bike for height if you're lowering the rear. I'm don't know how that's done on a CBR but I'm sure some members here will give you a better technical explanation. You can also try a CBR250 forum as others have mentioned.
Be very careful here, her being comfortable while stopped is so much less important than the suspension being happy while riding that it is almost immaterial. Dropping a bike at a light is embarassing, grounding a hard part and crashing in a corner can have much worse consequences. Make the changes to the seat/boots/experience, not the suspension.