Robert:
First of all, welcome to the club. Why put Alembic pickups in a Squire? At least you'll have the best sounding Squire around! You've got some nice pickups and electronics there. As for the question you asked, is the original input jack wired to anything? If so, then I would suspect an OBEL (onboard effects loop). If it's not wired to anything else, than the previous owner abandoned it when the Alembic stuff was installed. If you decide to install them in another guitar, feel free to ask any questions you may have or ask for tips. I've installed several of these sets, though I add a Q switch - that takes up the second tone pot hole and I use the original input.
If you want to sell them, this is a great place. I know I'd be interested. Either way, you scored.
Bill, the guitar one