I could not find the correct tail light bulb sockets so off to Napa and picked up a set of basic sockets for three bucks. Now, these are deeper than the depth in the 300 tail light assembly so I removed the innards and ground off the rear of the socket about an eighth or till the socket just touched the plastic base when inserted. The factory hole in the assembly is a tad small so I opened it up with a Dremel stone to take the new socket. The wire that comes with the socket is long enough to reach the point where the soldered connection is made. Easy to fish through the assembly to the original single tail light. I ground a small notch in the lower end of the bulb socket for the wire to come through.
The center piece bulb contact has to be bent ninety degrees to fit in the minimum space and point to the notch. Throw away the spring and place a small bit of foam rubber to replace the job of the spring.
A couple of pop rivets and the job is done or two part epoxy would work. There is no room for screw heads.
The book calls for 10 Watt bulbs. I have LED in the original and will install LED in the new sockets to keep the look correct.

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1984 300SD turbo 126
"My true love"

God made me an atheist and who am I to question His wisdom

I like the improved visibility that the extra bulbs offer.
Which LED bulbs are you using, and how do you like them so far? Is the tail lamp color similar to incandescent bulbs when they are illuminated or is it more "pink-ish"?

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2007 Dodge Ram 3500 Cummins Turbo Diesel 4x4
1994 GMC S-15 pickup 4.3 5MT
1985 300 SD
1978 300 CD
1962 220-S Fintail - awaiting restoration

As the LEDs might not be lighting the reflectors as the original did, how is the light output when you are offset from directly behind (45degrees etc.)?

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Gone to the dark side

- Jeff

The Sylvania Zevo LED bulbs are excellent. Similar or better light output than incandescent and actually designed with reflectors in mind. They also light up much faster. I haven't used them myself but my friend has some in his 1st gen 4Runner and Saturn SL1.

Here's a good demo of them:
https://www.youtube.com/watch?v=agemMUc2muE

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Current: 1975 450SEL, 83 300D, 88 Yugo GVX, 90 300D OM603 swap, 91 F150 4.6 4v swap, 93 190E Sportline LE 3.0L M104 swap, 93 190E Sportline LE Megasquirt, 03 Sprinter, 06 E500 4Matic wagon.

The LED are on the outside, a little on the weak side but when my wife slams the trunk lid shut the concussion won't blow the LED as it will the filament bulbs The LED in there now have a red reflective base.

__________________
1984 300SD turbo 126
"My true love"

God made me an atheist and who am I to question His wisdom