Still looking. I did find out that the Hella relay should be for the headlight washers.
I also dropped the sound shield under the drivers' dash, but cannot see anything of interest yet. And the only thing directly behind the radio is an a/c duct.
I tried to get out the one silver box above the ecm tonight. It was held in by one 10mm nut, which was removed easily. Getting the box out was another matter. There is absolutely no room to swing it around. The box sits above the ecm, behind the glove box, and to the left of the speaker opening. The wire looms are too tight on the right side to allow any space to be created. I nearly got my arm stuck trying to find a way to wiggle it out.
It might have more room if I unplugged the two connectors, but it is difficult to see the correct way to release without breaking any plastic.
Does anyone know what a 'newer' (post-92) anti-theft module looks like?