Not sure how many have FB or use it. There is info on doing this mod in the Technical Archives...
Impala SS Technical Archives
...and no idea how it compares to your method but thought it would be nice to include the Text here as well of that method...
Power Antenna Modifications
Allows you to force your power antenna to an up or down position to avoid problems such as having it freeze up in the winter or allowing it to stay down while you play CD's.
For a clean installation, you must relocate your lighter to the ashtray, as the 9C1 cars do.
The 9C1 switches (P/N ???, $??.00) that go in place of the lighter if you want the switches in the factory location OR
An easy and invisible solution is to put a small black rocker switch in the back roof of the "HOLE" (the change holder near your headlight switch. The switch should be flat black plastic and placed to be invisible. It can readily be switched by feel and if you ever want to remove it, all you have to do is get a new "hole" liner box.
Procedure (from Eric Woster ):
The dash needs to be slightly disassembled. The Instrument Cluster Trim ring is easy to take off, but the 96 service manual only shows 3 screws for the dash lower trim piece. There are 7 screws with 4 across the bottom, one in the ashtray, one by the glovebox, and one behind the left fusebox lid. You will probably need to remove the ashtray assembly to get to one of them. Getting the lower dash piece off is nerve wracking. Just make sure to get all of those 1/4" screws and unsnap it from left to right. Also keep track of where each screw comes from! Refer to the service manuals for details on dash disassembly.
If you are installing the switch in the "hole", remove the "Headlight Switch Panel". The "hole" unsnaps from the "Headlight Switch Panel".
Refer to the service manual wiring diagrams. Remove the convenience center 2 screws, (you may need to remove the "tall" audible alarm module plugged into the convenience center to get to the top screw).
Unwrap the black tape from the emerging harness and look at the wires coming from the lower connector. Find the smaller of the 2 dark green wires from the back of the antenna relay and find a good place to cut into the wire to put a switch in the circuit. This dark green wire is connected to the radio at pin 8 of the C1 connector, then it goes over to pin E7 of the big C200 connector under the LH side of the dash, and from there it goes to the Power Antenna Relay connector at pin B.
Using compatible crimp-on connectors allows you to disconnect the switch from the circuit and attach the 2 ends of the original wires back together if you ever want to. Run your switch wires to where your switch will be.
If you are installing in the "hole", Install the switch by cutting the the far right roof of the "hole". A little Dremel Moto-Tool with a cut-off wheel makes it easy to cut the plastic accurately. A snap-in type switch makes it easy to install in the cut hole.
If you are using the 9C1 switches, remove and relocate the lighter to the right side of the ash tray. Replace with the new switches and wire them up. The diagrams for the switches are in the service manuals.
When reinstalling the dash trim pieces, put in all the screws before tightening them. As you tighten them, gently pull back and forth on the close area of the dash and tighten just past where it stops rattling/creaking.
The antenna only goes up when the switch is flipped, and if it is flipped after the Ant. is up, it immediately goes down.