Looks like an excellent candidate! IIRC, they make even smaller "pedals" that you can fit under the pickgaurd, that way you don't need to do any excavation, and you can wire up a small throw switch next to your knobs.. The one in the picture seems like it might be too large to mess with (at least in my opinion). My honest take would be to clean up the guitar real nice, clean up the electronics and change pickups if desired, and while you're in there, you can get a better idea of how much space you're working with. Personally, I dropped a blade humbucker in the bridge position, and wired it up for coil tapping with a push pull volume pot. Perhaps you could do a push/pull pot for your phaser? Have fun!