Somethings come to mind: Cranking or not cranking voltage at the coil, Battery condition and voltage at the positive junction on the rad support, If needed run a jumper (*Temporary) from the battery positive to coil to get car running and moving.
With Ing "ON" at Keyswitch,; "lift" the terminal lug from the coil and recheck, Using "sharp" pointed Meter leads back probe the resistance wire in the engine compartment (From Coil to bulkhead connector), then it turns into a pink wire from the interior of the bulkhead connector to the fuse block tang marked (ING) check voltage there also, Check for voltage at the Horn relay also.
a classiccarwiring.com color diagram helps a lot