[B][/B]Well took me awhile to get back to this post, but it's [B][I]sharing time[/I][/B]!
First you will need ONE [B]spare[/B] Tail light Curcuit board (GM#[B]16532713[/B]). I got mine from Ebay for $17, but a salvage yard may be a cheaper option?
Use this is the opportunity to practice on the [B]spare[/B] curcuit board as we also need to repeat some of these steps on the [B]stock[/B] curcuit board.
Simply pry open the [B]spare[/B] curcuit board using a thin flat screw driver to reveal the guts.
Now that you're familar, open both of your [B]stock[/B] curcuit boards.
On the [B]spare[/B] board, again practive removing the Brake & Turn sockets (Top/Center) by drilling the melted plastic rivit points and prying the sockets up off the electrical contacts. Some down pressure on the electrical traces was needed to prevent unwanted bending of the traces.
Repeat on the [B]stock[/B] boards, but ONLY remove the TAIL (center) socket.
Now we'll need to ADD the missing contacts to one of the TURN sockets to match those of the BRAKE socket removed from the TOP.
We will be able to use the [B]spare[/B] BRAKE socket so we only have to [I]make[/I] one.
We will make another BRAKE socket by adding the contacts of the [B]spare[/B] TAIL to the [B]stock[/B] TAIL socket.
Remove the metal contacts from the [B]spare[/B] TAIL socket.
Now we get a bit artistic. Take a pair of needle nosed plyers and [B]reverse[/B] the bends of the metal contacts from the [B]spare[/B] socket.
Next we need to add a jumer for the ground contacts.
Remove one of the contacts from the [B]stock[/B] socket and add a "U" shaped stripped wire into the contact holes.
Add a power lead wire (~4 inches) to the other contact and insert the new contacts. Pinch them back into the socket using the needle nose plyers.
Solder the connections.
Insert bulb and visually verify your new contacts make good contact with the bulb.
Now just build the other new socket using the same steps from the [B]spare [/B]BRAKE socket. (No fancy bending required)
Install the new sockets back on the [B]stock[/B] curcuit board. The trace contacts will be VERY tight now because of the added wire on the ground contacts. I used the empty [B]spare[/B] socket placed upside down on the [B]stock[/B] socket and tapped lightly with a hammer until the new socket was firmly replaced over the plastic studs.
Strip the new tail power wire and solder to the [B]stock[/B] curcuit board. Note that the board has very little clearance right here so strip plenty to reduce the wire diameter in the tight spot.
Quick Test: Plug the modified board into your truck's harness and witness your creation. [B][I]IT'S ALIVE [/I][/B](hopefully)
Then just put it all back together.
I used a plastic weld product. After mixing, I placed a generous bead on the studs we drilled out eariler to secure the socket. Then applied a bead of plastic weld along the entire OEM sealed edge and replaced the cover.
Cure time is 90 minutes so no need to rush.
Don't forget to replace the rubber gaskets around the bulbs. Then tighten the modified board back onto the tail lens. This creates uniform pressure on the three sockets while your new weld cures and should make a water tight seal along the edge of your new weld.
Here's the look when complete.
Took me about 4 hrs, but most of that was
So, with some of the surprises removed, you can probably accomplish this mod in a hour or so.