I've started refurbishing a pair of AR4x speakers that my father bought new along with a Fischer 500c. I thought this was in 1966 but the serial #'s on the back don't match this date. Maybe he bought the Fischer in 66 and the speakers at a later date, though that doesn't really make much sense to me. The #'s are FX44345 and FX44459. Can anyone help me place the date of these? The odd thing I've found on pulling the woofers is the wax capacitor has three wires coming out of it, a black green and