Troubleshooting coolant gauge - CE1 pinout questions

[wolfsburged]

Before tearing the motor out for rebuild, I had the following issue with my coolant gauge in the cluster:

With the wire (yellow/red) connected to the nail-head temp. sender, and ignition power on, gauge would slowly rise and peg, then the light would start flashing. This would happen even if the engine was not running and cold. If I disconnected the wire, then the gauge would go to approximately 1/2 way.

I connected the wiring from my VDO oil temp. gauge to the coolant temp. sender and it seemed to read correctly (80-100 C, with fans kicking on at 100C if sitting, and dropping about to 80 C).

So I believe the sender to be ok. Obviously there is any issue with the wiring for my coolant gauge. I assume it be to be prior to whichever relay controls the coolant low sender/overtemp LED.

Looking through this resource:
http://www.a2resource.com/electrical/CE1.html

I have a few questions on how to interpret this data. I see the Coolant Temp. Gauge referenced twice.

B07 - Gauge Cluster (Coolant Temperature Gauge), Yellow/Red
and
D29 - Coolant Temperature Sender, Yellow/Red

Am I to assume that the wiring goes:
sender -> D29 -> LED relay -> B07 -> back of cluster

Such that I ought to check continuity between the sender and D29, then between D29 and B07, and then between B07 and the cluster? And somewhere in between I will probably find a short to ground?

Also when looking at the back of these connectors at the fuseblock, how are the pins numbered? I.E. how do I determine which is D29, B07, etc?

Thanks in advance!