Guys, I've had several McCartys and had BKPs (and other) pickups in them.
The neck cavity is deep enough to fit long leg pickups in, but the bridge isn't. I had to send a brand new pair of Cold Sweats back to BKP to have the baseplates swapped.
This was an '08 McCarty, and when I fitted BKPs to my '01 McCarty the short legs were just right too. I don't think the cavity routing has changed over the years.......