I have acquired a couple of secondhand sets of Alembic pickups and am wondering if it's possible to sand down the tops a little to remove nicks, string marks etc - just generally smarten them up. I've tried this once before with a non-alembic pup with similar-looking construction and the plastic casing faded when I sanded it so it wasn't uniform black any more. I wondered if anyone had any experience of trying this on Alembics?