I don't know if I'd consider the Antiquity an upgrade, so much as walterw put so perfectly as a sideways move. Sure, it may be a little different, but likely not significantly better. Those CS are damn good pickups. Swapped mine out for a Fralin, kind of thinking I'd like it more as I've always had great luck with them, but the old pickup is going back in. Definitely had a bit more "oomph". That said, the Antiquity might be exactly what you're looking for...won't really know till its in.
Watch some YouTube vids on soldering, make sure you have a decent iron (45-60 watts is perfect), make sure it's tinned, CLEAN and HOT as hell. Maybe try practicing on some old pots until you get it down.