Something aint right there. You should have a cable that plugs into the amp that has two connectors coming off it. One goes to cd one goes to tape player. There then should be two connectors (power) that plug into each. The Amp sits under the dash on passenger side and should be a mounting plate here. You should find a power plug there and a speaker plug. That should be it.
I have a cable in mine i can check to see if there is a part number on it. Cheers Ian