pink resistor wire? resides where? 1 wire alt upgrade recommendation?

[67resto-coupe]

since i've been having issues getting my '67 coupe to run consistently, i've rebuilt the carb, installed a new tank and thought i was on my way to cruising bliss. but then my car died several times on a cruise around the 'hood. a local mustang shop asked if my coil/dist was getting a full 12v connection. i don't know. i think so. how could i check? i borrowed a meter thingy. the shop told me to look for a pink resistor wire, but in following my + coil terminal, i could only find a red wire w/a green stripe. that goes all the way to a pigtail coming out of the firewall and it joins to another red/green wire, no pink.

is this phantom pink wire under the dash only? is there a way i can use the meter to check the voltage going thru the line? i guess i could stab the pigtail coming out and touch the + terminal? i don't want to fry anything, so your help is appreciated.

maybe my alternator is dead? any tips on brand? amp output 100 or 140?

thanks.

 

[jims6t6]

it's under the dash close to the ign switch

 

[Midlife]

Rather than trying to trace wires, why not put the key in RUN and measure the voltage at the coil? It will either read about 9 or 12V (with or without the resistor wire) or 0 if it happens to be in a certain location of the distributor. If so, simply turn the engine a bit.

Or run the engine and measure voltage...