Questions on Rallye dash wiring

[furious70]

I'm working on the parts to convert the standard dash in my 72 SSP cloned into a RR.
I have a 74 dash assembly with 120 speedo and oem tach.
I have a 72 charger wiring harness for a rallye dash with the oem clock.
and my 72 car.
Questions in no particular order:
1. is the black with tracer wire labeled clock (I labeled it) the power wire for the clock?
2. the 72 voltage regulator and harness for it seems to be a bit different than the 74 one on the cluster as the 72 as an extra lug on it that attaches to a wiring in the harness. I assume I can just use the 72 one?
3. Did the blower motor switch plug layout change 72 to 74? I think I have identified the correct plug in the harness but it's a different shape than the switch from the 74.
4. Among all the orange bulb wires is there 1 tan one that is nothing but a cluster light?
5. The yellow triangle things - are they the accessory feed provisions that I should get power for the tach from?
6. Is the post on the tach for power and the other bigger nut is for the lead from the negative side of the coil?

 

[mrmolding]

I don't know if this helps, but in addition to a FSM, this thread about post #51 has been a visual guide for me on three cars. Great pics on what is what in a harness:
1971 Speedipus Rex

 

[furious70]

Wow that's quite a thread, thanks!

 

[Nacho-RT74]

I'm working on the parts to convert the standard dash in my 72 SSP cloned into a RR.
I have a 74 dash assembly with 120 speedo and oem tach.
I have a 72 charger wiring harness for a rallye dash with the oem clock.
and my 72 car.
Questions in no particular order:
1. is the black with tracer wire labeled clock (I labeled it) the power wire for the clock?

Clock gets it’s own wire from amm black post. Not related to harness since harness is basically the same for all diff cluster options. Tach and clock gets extra harnesses/wires for their function.

Black traced wire must be pretty sure (and as far I recall) voltage limiter ground. Voltage limiter gets two black wires, one of them with wider terminal for the bracket prong ground. In that way you can’t connect accidentally the VL positive source coming from ACC source of the Ign switch source (from fuse box) to the VL ground. So you can check which one is the wider plug (black or black traced) and that one goes to the VL bracket prong.

The other end of the ground is attached to a ground provision on dash frame with a J nut… as far I recall, far left down the dash, close to the emergency brake handle area.

2. the 72 voltage regulator and harness for it seems to be a bit different than the 74 one on the cluster as the 72 as an extra lug on it that attaches to a wiring in the harness. I assume I can just use the 72 one?

As mentioned, the basics of the cluster connection is pretty much the same on all 71/74… HOWEVER, every year harness is DIFFERENT in something so the full underdash harness IS NOT 100% a straight swap work. The closest between them are 72 and 73. But on the cluster end, all 71/74s are the same.

I can provide more details about the diff years diff if requested. But having a 74 the bigger (if not saying HUGE ) diff is the interlock and warning signals system

3. Did the blower motor switch plug layout change 72 to 74? I think I have identified the correct plug in the harness but it's a different shape than the switch from the 74.

The change over happened between 72 and 73.

71/72s get also in fact double face light bulbs while 73/74 are single. Just reuse your full 72 A/C control unit from the standard cluster installing it on the rally cluster. They are the same between rally and standard clusters

4. Among all the orange bulb wires is there 1 tan one that is nothing but a cluster light?

Tan and light green wire sockets are directionals (left and right) pilot lights. As far I can tell I think you have an orange wire light where the tan should be on tach… and the empty cavity should get the orange.

5. The yellow triangle things - are they the accessory feed provisions that I should get power for the tach from?

Yes, also for rear deffog if equiped, and also A/C clutch. 71/72s got more accs than 73/74, hence they get two Acc yellow feeds

6. Is the post on the tach for power and the other bigger nut is for the lead from the negative side of the coil?

Personally can’t recall, LOL BUT is on diagrams.

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[71Beeper]

Furious - here's some pictures of the back of my ralley dash that went into my 71.
I have the re-pop tach in mine so I had to purchase the wiring kit for that.

My heater controls are 1971 so it will be different than the 72's & up.
Nacho is correct that they use 2 bulbs to light them up at night.

I also added an additional ground wire from the back of the cluster down to the mounting point of the dash - down near where the parking brake release handle is.

 

[Nacho-RT74]

71 and 72 A/C-Heater controls are the same, then It comes 73 and lates

 

[furious70]

I'll be able to use the ac controller in the car then and it should match the wiring

 

[Nacho-RT74]

Yes sir… just keep your 72 control. Will bolt in straight up.