You'd be much better off with a Bentley 240 manual.

"Re the socket under the dash - maybe there is a male plug w matching wires hanging up there and they are disconnected. I will look. 2 of the wires are Y/R that are fuel pump/relay wires."

I recall a 4-pin plug that carries the Y/R wire and also +12V fron fuse #12 to the fuel relay coil when the key is On. The wire colors might change at that plug—Blue/Yellow from the fuse, Blue/Red to the fuel relay. But I recall that plug being over near the ECU. And it wouldn't have "5-7 wires". Where are your fuel relays (System and Pump) located, just out of curiosity?

I'm not sure about the coax shielding, but I think it's to prevent extraneous signal pickup in those lines (as opposed to reducing radio interference).

Re:"I have to repair one of the grey wires from coil #1 and its crimp connector where it connects to the pair of White w Red stripe single conductor wires. One W/R goes to ICU and one W/R connects to another grey to the ECU. .
I will reconnect only the center hot conductor from grey to the W/R pair."

I'm also a little shakey about those wires on Coil #1, given the other wiring "mods" you've got.
You say: "One W/R goes to ICU and one W/R connects to another grey to the ECU." But That doesn't agree with th diagram. The only thing from the coil #1 to the ECU is one of two "whites", which are probably the "grays" you refer to with the shielding and outer gray insulation.
Here's what the diagram shows for Coil #1:

The two (fat/coaxed?) "grays" (diagram shows these as shielded White)
1) to ICU #1 to initiate and time the ignition
2) the other to the FI ECU #1 to allow fuel operation

The two R/W should not be needed, or only one of them if you have a tach. Can't see the need for another R/W unless it was in the (common?) harness for the K-jet system, where it would go to the Fuel Relay to serve the same "allow fuel" function as in 2) above.

Which suddenly reminds me that the K-jet Fuel relay has 6 pins and is (on turbo cars) over where you found that empty socket. Maybe the cars of that year were wired for both K-jet and LH, leaving some stuff dangling, and some wired but unused (like the two R/W at coil #1). You might even find a dangling R/W behind the inst. cluster if you don't have a tach installed.

And—"The ICU and ECU and impulse sender will provide the "make and break" unless one of these is faulty, right?"

Not quite right. The LH ECU has nothing to do with the "make and break" at the coil, but it does use (needs is a better word) the make and break impulse (weak signal) as "permission" to activate the FI system. That's a safety feature. Spark trumps fuel, so if you're upside down in a ditch there will be no fuel pumping fuel to a dead engine.

The ICU provides the "make and break", the Hall switch impulse tell the ICU "when to do it".
When the ICU does the "make and break" at coil #1, that same "signal" goes to the ECU to enable FI operation.

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Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.