American Motors: Sorry...It is a 1969 AMX...., mallory hyfire, factory tach

Question
Sorry...It is a 1969 AMX. I figured out the Alternator abd VR but still havent got the Tach working. The only wire coming out of the HyFire to the tach is yellow...but not sure which wire to hook to. The car was rewired several years ago, and red wire was very popular. Can I bypass the wire harness and run new wire to the tach? If so, how does it hook up? The wiring diagrams do not even show a tach.

Mark


Followup To
Question -
I just replaced my Leece alternator (built in Reg) with the correct Alternator from Advance Auto. I had to buy a new regulator to make it right again but it didnt come with instructions. The reg is labeled F 1 2 G respectively. How do I know which wires go where? The diagrams arent much help cause they assume stock. Also, put in a Mallory HyFire and now the tach doesnt work? I have a Blue and  a Yellow wire at the selenoid left over and no Idea where they go. Please help!
Answer -
I apologize, but my specialty is in vehicles manufactured by American Motors Corporation. i.e. Matadors, Gremlins, Pacers, AMX's,etc. I do not have any experience with Leece alternators. Not knowing what kind of vehicle you are working on, I would recommend finding a wiring diagram or repair manual of your vehicle to check for proper wire routing. I am not familiar with Mallory HyFire, either; just plane old AMC cars. Sorry.
Kevin

Answer
OK,
I found the correct wiring scheme for your tach. Pretend the Hy Fire isn't there for the time being. Your factory tach has two wires, yellow(-) and blue(+). Originally,the yellow should run to the (+) side of the coil, the blue to the "I" terminal on top of the solenoid. There should be two small terminals on top of the solenoid, one wire runs to the ignition switch(green w/tracer), the other terminal designated "I" (blue or yellow) runs to the (+) side of the ignition coil. If you hook it up this way and it doesn't work, move the yellow wire of the tach to the (-) side of the coil. As for your Hy Fire, if you still can't get the tach to work, let me know the model Hy Fire you have. Mallory has installation instructions online I can look up. I am looking at an OLD wiring digram for a 69 AMX. Hope this helps, let me know.