TR4/4A dash gauge light wiring

[JimTR4]

Hi all,
Can someone clarify for me please? I have the wooden fascia off my TR4 for replacement, also replacing a broken fuel gauge.
There's a wiring loom that is a division of a larger loom. tI carries the ammeter wires, a fuel gauge and a water temp gauge wire. Also in that "sub" loom there are 3 black wires. Those 3 wires have been (badly) cut off and taped up.
I'm assuming they are ground/earth wires as they're black.
Can someone clarify if they are supposed to feed the gauge lights or where they are supposed to go.
The lights on the gauges did work but their ground connection seems to be from the ammeter light to its knurled knob that has been made fairly recently (crimped eyelet connector).
I'd like to clean all this up while the dash is off.
Thanks.

 

[Geo Hahn]

I recall a daisy chain of black wire with ring connectors that provided grounds to several spots behind the dash. In particular I recall ring connectors under the thumb-nuts for the mounts of the speedo and tach as well as some of the smaller instruments.

Possibly the dash lights work okay w/o that ground but it is good to have there to assure a good connection.

 

[JimTR4]

Yes, there's a small daisy chain of 3 ring connectors that goes across the gauges.
The battery is out but I checked continuity and the 3 black wires do seem to be grounded, so I think I'll use them for grounding the gauges. Cant do any harm i think. Strange why they were terminated though.

 

[Kev1]

https://www.advanceautowire.com/tr24a.pdf

These prints might help