I don't know much about Schecters, but would I be right in thinking your guitar's a seven-string with the big rectangular soap-bar style EMGs?

I don't think the BKP seven-string pickups will fit easily into those cavities - they're shaped more like conventional humbuckers. They may drop into the cavities but leave big gaps in the corners, or they may be wider than the EMGs (like humbuckers are wider than P-90s), in which case you'll need some extra routing.
You'll might want mounting rings to make it look better, but then you might also need to partially plug the existing cavities so the mounting rings have something to attach to.
A job for a pro, probably? :(