I just reported that the mod worked. (I left it in the garage without even starting the car before reporting success)
I went to my car later after dark for first start. Headlights and driving lights flashed for a second when I turned them on-then went dark, highbeams=NO! Now nothing but parking lights. DONT DO THIS MOD
Replaced fuse # 18 (10A) by drivers knee. Returned wires to prior. All works as before.
I think they actually blew as I put it into reverse. I think it has to do with changing polarity on the map lights. I jumped in, started it, dropped into reverse before interior lights had a chance to dim.