I mounted mine by my left knee where the factory switch blanks were located. I didn't have to cut or drill any of the factory plastic either with the recessed mounting hardware.
I removed the 4 factory switches in this location and relocated 1 to the upper switch location (wiper heater switch needs to be flipped upside down in order to fit this blank) and 1 to the lower single switch blank.
All i used was longer #1.5" x #6 machine bolts (in lieu of the supplied all-thread) and nuts to clamp the mounting brackets to the backside of the plastic.
Pretty satisfied with how clean it looks, although i have yet to install the SP-8100. I was debating mounting it vertically on the left plastic pillar below the stereo, but I didn't think it would look as clean/factory.
View attachment 242077
View attachment 242078