[fun in dirt]

We had similar thing happen ... '55 gasser, that shakes, rattles & vibrates alot when running. Zero issues for the last year or 2 running it. Went to town in it the other day & get back in and will not crank. End up standing on my head to get under dash, wiggle & push in on connector to ignition switch while husband turns key & it cranked right up. So get home & investigate - melted plastic connector around the red main power connector on ignition switch. New ignition switch, new plastic connector cover & all has been good since - I honestly think it was the Chiner made ignition switch; that blade in switch became loose (from combo of cheesy made and car vibration) and loose/broken connection can cause excessive heat making it melt plastic & multiple other problems. I had no luck finding a heavier made non-China switch anywhere,which is a freakin shame, but new one felt solid as Chiner made can & has been good since, but I will keep an eye on it.