my car is a 1984 Mustang 5.0 it is carbureted and has a manual transmission and duraspark II ignition. I just put an alternator from a 98 mustang on it and now it won't start. It turns over fine, but it is not getting spark. The green/red wire to the coil only gets 1.7 volts with the key on. When you turn the key to the start position, it goes up to 2.3 volts.