Hot Rods Adding a 3rd Brake Light

I want to add a Ford style taillight to the rear dash of my '50 Plymouth to be used as a 3rd brake light. Does anyone make a premade wiring harness or know how to wire it in so that it doesn't flash with the blinker? I really don't want to plumb in a second switch into my brake line if I don't have to. I am beating my head against the wall trying to figure it out!

 

You have to run a wire from the light to the brake terminal on your existing brake light switch, byp***ing the steering column wiring altogether.

 

Perfect thanks!!

I knew i was totally over thinking this!

 

Or to the brake switch input wire at your turn signal switch, whichever is easier.

 

I use various old tail lights for 3rd brake lights. Wiring described by Jim B. is accurate and probably easiest.. I hook both wire leads coming out of the light together and put two bright bulbs in the light. I have one on my A-V8 that is so bright it could likely be seen from the moon. Or someplace..........

 

I don't think you are going to like lighting up your entire rear window when you hit the brakes at night. I would get it as close to the window as possible to lessen the effect.

 

We just did one on my buddy’s shoebox, it mounts like a fog light on the rear bumper.

 

Another style, may not be right for 1950 trunk lid:
https://www.ebay.com/itm/3631475651...oc:2&msclkid=96d08e4395c519182fd4eda227195c8e

 

This 3rd brake light is for a 46-48 coupe. The curve of the trunk lid on a coupe is at a lower angle then a 50 coupe would be.
I suspect the 3rd brake light from a 46-48 Plymouth sedan is mounted more vertical and might match the angle of a 50 Plymouth trunk lid better.
Either way, you will be drilling holes in your trunk lid, I suspect.

 

Not trying to be an ***, but..... Where exactly is the rear dash located?

 

That's where we as kids lay up there like a cat on family rides, "It's my turn!"

 

I'm gonna **** up my 39 with a 3rd light. I'm adding an LED. Yup, I said it. "JOCKO! WTF! NO!!" Ok, ok. You won't see the light itself but if it works half as good as I think you'll never miss it. I hate LED ****, but the light was free, bright as ****, small, and I'll paint all the chrome semi flat black and make it go away.

 

'package tray' below the rear window.

 

Any 3rd brake light mounted inside of the p***enger compartment that is not sealed to the rear window is going to light up the entire back 1/2 of inside of the p***enger compartment, and will also reflect off the inside of the windshield at night, LED or not.

Want to test that thought before you spend money? Tonight, after the dark of the night, get in your car, close the door, point a flashlight at the back window and turn it on. Does all the light reflecting around inside the car bother you? A 3rd brake light will light everything up in red light just like the flash light did in white light. The closer you get to the back window, the less reflection, but unless its sealed against the gl***, its still going to be there. A helper holding the flashlight and moving it towards the rear window more would prove this point too.

You are going to "see" it every time you step on the brakes.

 

I went through all this on my Stude, and a '64 Dodge. You're right, but some creativity will net a solution. Do what the factories do, create a tunnel that seals the light to the gl***. I don't have access to either car to snap a pic, but hopefully you catch my idea. Mine are rectangular, but maybe with these lights, a section of thin hose or duct about the diameter of the light, cut to fit the back gl*** angle.

 

Years ago I bought one of those cheesy 3rd brake light kits at a garage sale for 25 cents (I think I got screwed, its still hanging on the wall. LOL!). It had a 2' long piece of the self stick foam square stuff included in the kit. You could either stick it to the gl***, or to the light to seal it against the gl***. How long the double sided tape would actually work would be anyone's guess.

I have an LED 3rd brake light on my coupe, its above the rear bumper and its bright. I drive it a lot a**** the natives, I'd rather have a better chance of being seen. My taillights are also LED.

 

Package tray ..

 

Nifty idea. Model A's 4 ever
A thought to anyone going with a 3rd light, especially LED.
When you have it in place, put a test driver in the seat, During Daylight.
Then walk back 30 paces and signal them to hit the pedal.
You'll then know what message you send to the auto-pilot driver

 

I am planning on making a housing for to sit inside that is sealed against the rear window.

 

I have been looking for one of those as well, just waiting for the swap meet season to open back up.

 

Package tray, bobbing head dog shelf, curtain crawler containment unit (old school baby bag storage area)

 

A selection of outside mounts lights here:
https://www.ebay.com/sch/i.html?_nkw=vintage+red+stop+light&_trksid=p2332490.m4084.l1311&_sacat=0

 

I have an old wig wag lamp I wanted to use as a 3rd eye because my taillights are so low on the rear of my Austin g***er. But tried the light after rewiring it, and it just lit up my back window too bright to see well. I ended up buying a dreaded LED strip that bolts to my license plate, and sort of blends in until I step on the brake. At least nobody notices it when I'm driving until I touch the brake pedal, and then they really notice it; which is great.

 

here is the light i am going to use on my 39 chevy truck build. i bought it on ebay $400 then spent a couple hundred on making the swing part work and then about 800 doing the chrome on it

 

I wired my 3rd brake lite into my left turn signal, that way when sitting in the highway trying to make a left turn the 3rd brake lite plus the left turn signal are both flashing at the same time to warn on comming traffic from the rear.............