HELLO DAVE, DON'T KNOW IF YOU DEAL WITH ANY EDSEL FOLKS. IF YOU DO YOU MIGHT RUN THIS BY THEM:

UNIQUE TO THE '58 IS A SEPARATE DASH LIGHT DIM / BRIGHT SWITCH THAT IS UNDER THE DASH, RIGHT OF THE STEERING COLUMN AND HIDDEN FROM VIEW. THIS IS BECAUSE THE HEADLIGHT SWITCH IS A TOGGLE SWITCH THAT ONLY TURNS ON AND OFF, WITH NO CONNECTION TO THE INSTRUMENT LIGHT DIMMER.

THE ORIGINAL FACTORY SWITCH WAS NO GOOD FROM DAY ONE ------THE SPRING INSIDE WOULD MELT LEAVING THE DASH FULLY BRIGHT OR FULLY BLACKED OUT WITH NO WAY TO ADJUST THE LIGHTS. OVER THE YEARS I'VE PULLED 6 OR 8 OF THESE OUT OF PARTS CARS AND EVERY ONE WAS BAD---------NOT ONE OF HENRY'S BRIGHTER IDEA'S FOR SURE.

THE ONE IN MY '58 WAS BAD WHEN I GOT THE CAR AND I WAS LUCKY TO FIND AN N.O.S. SWITCH, IN THE BOX, DOWN AT THE SAN DIEGO AUTO SWAP MEET. PAID BIG BUCKS FOR IT AND GUESS WHAT? PUT IT IN, USED IT TWICE AND IT BURNED OUT TOO!!!!!

A FEW YEARS AGO I BOUGHT A 1991 MITISUBISHI PICK UP FROM A FRIEND OF MINE, THIS THING WAS LIKE NEW WITH LOW MILES AND I BROKE MY VOW TO NEVER BUY A JAP RICE ROCKET. THE FIRST TIME I DROVE IT IN THE DARK THE DASH LIGHTS SURE SEEMED DIM AND THERE WAS NO WAY TO GO HIGH OR LOW WITH THE LEVER ON THE STALK. HALF WAY HOME I GOT TO THINKING THIS THING COULD HAVE A SEPARATE SWITCH LIKE THE EDSEL, SO I REACHED UNDER THE DASH IN THE SAME PLACE IT IS ON THE EDSEL. THERE IS A NEAR IDENTICAL SWITCH, IN THE SAME PLACE AND GUESS WHAT-----IT WORKS !!!!!!!!!!!!!!!!!!!!

THE HOLE THRU THE DASH BOTTOM REQUIRES BEING REAMED OUT SLIGHTLY BUT OTHERWISE IT'S A DIRECT PLUG-IN REPLACEMENT FOR A COUPLE OF BUCKS AT THE BONE YARD, AND EVERY ONE I HAVE FOUND, UNLIKE HENRY'S, WORKS!
IF YOU KNOW OR DEAL WITH ANY EDSEL GUYS, YOU MIGHT RUN THIS BY THEM. THE LITTLE DODGE DURANGO PICKUP IS THE SAME AS THE MITSUBISHI PICKUP AND YOU CAN STILL FIND THESE IN THE JUNK YARDS.

HOW THIS CAME UP NOW, AN EDSEL OWNER FROM UP IN SANTA BARBARA HEARD ABOUT THIS FROM SOMEONE IN THE FAB.50'S CSR CLUB, AND GAVE THIS GUY MY PHONE NUMBER. SEEMS HE HAS BEEN DRIVING WITH NO INSTRUMENT LIGHTS FOR 17 YEARS. IT TOOK ABOUT 3 MINUTES TO SOLVE HIS PROBLEM---------------HE DIDN’T KNOW THERE WAS A SEPERATE SWITCH AND THOUGHT THE HEADLIGHT / TAIL-LIGHT TOGGLE SWITCH WAS BAD. TO ADD INSULT TO INJURY, HIS SWITCH ACTUALLY WORKS---------THIS IS THE ONLY ONE I’VE EVER SEEN THAT DOES!!!!!
I GAVE HIM ONE OF THE JAP UNITS AND I'M SURE HE WILL NEED IT SOON.------------TONY.

Thanks for the heads-up, Tony. The only insight I can add is this: That wire-wound resistor is made from ni-chrome (nickel-chromium) wire, usually mounted on porcelain (for high heat).
If you put too many (or higher wattage) lights in the dashboard circuit, the wire-wound resistor will overheat and burn open. Ford should have used thicker wire for a greater load.

My 1990 Mustang has a separate dash dimming wheel, mounted just left of the column.
Dave