Doesn't make sense to me to hold the wires in place while inserting the motor housing through the firewall, as the wires exit the end of the motor housing. With the wires taped to the sides, either the plugs themselves were taped, in which case the wires could catch on the housing, or if only the wires were taped, the bullet plugs would catch on the housing. IIRC, it's a fairly tight fit through the firewall hole.