It's Alive!!!!! And Of Course, A Question...

Hey all, I finally got my mustang running again!! Whoo hoo!! The only problem I am having now is I am having a hard time finding a good 12v switched wire to turn my msd on and off with. I tried the wiper motor feed wire, and another misc. switched wire, both were no good. They both had a good 12v when the key was on-not starting, but when I started the engine, the voltage dropped too much to fire the msd., hence, no spark to the plugs...So when I ran the switched 12v wire from the msd box straight to the battery, the car fires right up, but I loose the on/off with the ignition switch. Do I need to make up a relay, and run the switched wire to the msd off of that?? Jrichker?

I converted to carb, and removed the old computer and oem ignition. I am now running the msd 6al box with a blaster 2 coil. I also ran a Mallory 3 port fuel pressure regulator with a return line to the tank that was made for converting high pressure fuel pumps to low pressure carb setups...works great, I can adjust my fuel pressure anywhere from 2-12 psi by turning a knob. I am currently running 6 psi to the carb.

on the left inner fender well