I need some help with the wireing of an underdash mounted 8 track player. I can find no stamped numbers on this unit it, does have 7c40b28b01 on the side in very small letters, not at all what you normally see on radios of this vintage. I have searched al the Ford wireing books from 67 to 73 and find no reference to an underdash unit. This unit has two four wire plugs and three wires that have apparently been cut. One plug has three male (yellow,red,black) and one male (orange). The other four prong plug has three female (green,purple,white) and one male (black). The three cut wires are black (2) and purple. I am at all sure why this unit would have so many plugs. I'm sure some are ground (unit and speakers) power, and speaker and then maybe connection to the radio for the amplifier? Any way all help is apprecieated. Thanks.