[KappaKittyCat]

In terms of declawing cats, it's generally bad news because it can cause litter box problems down the road. Imagine that you'd just had all of your toes amputated at the first joint and you had to dig in and squat on gravel to pee. That's what it feels like to a newly-declawed cat. Though she might not have litter box problems right away, they could crop up when she's in a stressful situation, e.g. a move, an illness, or a new animal in the house.

I would especially discourage you from declawing a cat who's already six years old and has learned to live with his claws. It'd be way too traumatic, and he could undergo a major personality change.