[brucepick]

Did some experimenting myself today, on my very similar '97 HX.
I decided not to cut wires, but to get a second alt connector and splice my own scheme in between that one and the original one.

My car has a belly pan so getting at the alt from below is very cramped, working through the oil change access port.

Working from above, I finally got the 4 pin connector off the alt and stripped back some of the protective covering over the 4 wires. To get some flexibility and access to the individual wires.

I kept looking at it and finally decided I didn't have enough working room to be able to splice on my own wires after cutting the existing ones about 1 inch back from the connector.

Thus, I'm back to a plan I suggested earlier. Here goes.

Get a junkyard to sell me a connector from a matching car. It's female, and goes onto the alternator. When I'm done attaching what I want to the four pigtails on the junkyard connector, it will go on to my alternator.

The connector has four wires. Two of them will be restored to their regular path: I'll crimp 1/8" male spade connectors onto those two wires on the junkyard connector. The spades will go onto my existing connector, in their matching locations; two connections restored. The other two wires on the junkyard connector will get long leads that go to a dash switch and then back to the engine bay. There they will get the same 1/8" male spades, then will be reconnected to the original alt connector that's part of my car's harness. When the dash switch is closed ("on"), the connections are restored as original. Switch off, the two wires are effectively cut.

I can push the spades into the alt harness connector; that's doable. What I can't do is cut those 4 wires on the original connector and then solder or crimp my extensions to the cut ends. No working room down there.

Unfortunately I didn't think to start the car with the connector pulled. I closed it up in a bit of a hurry to do some errands with my wife. Tomorrow I'll see about pulling off the alt connector again, to verify that it will disable the alt and not give a check engine light. But I suspect that will work fine, as long as I can get it pulled off.