Help me find a spot to hide my amp...please

I've got a 2k1 4runner sr5 with out the JBL system. I'm building the sub box to go behind the second row seat, have done the head unit and internals, now I need a good place to hide the amp. It measures 12"x8"x 2.4" in height for reference. I wanted to put it under the driver side seat and mount it to a piece of ABS plastic then wanted to mount that to the seat frame holes but they are odd in position, not just four hole straight down on the floor and the floor pan isn't really flat under there. So my next place I was thinking was on the driver side in the rear panel behind the second row of seats. Has anyone done this? I know there's plenty of depth just by measuring, but I haven't taken the panel off yet to see what I've got. I was also thinking about using that little cubby on the passenger side but I actually have stuff in there and use it so that's really out. I'm not going to bolt it to the box or mount it to the back of the second row seats either. Any suggestions?

I recently mounted an amp under the front passenger seat in a 4Runner. The amp was actually mounted to the seat frame itself which kept it up off the floor and there was enough clearance that the seats could still move without touching the amp... it was very similar to this install from 'Sounds Good Stereo'
It starts at 11:30
https://youtu.be/deEZx_6PVwE?t=692

I'm trying to picture how you mounted it to the frame? Did you mount it to cross beams underneath the underside of the seat? You're saying you didn't use the mounting holes that hold the seat down to the floor pan?

That's really cool, thanks for that. I hope the seat is the same way so I can do this, that works.

Since I'm out of town for work I'll have to see how much room I have underneath to do this when I get home. Watching that video made me go on ebay to look up seat frames and how I may be able to attach this to it. Since there is a natural slit in the carpet for the wires for the electric seat that gives me a place already underneath it to run them down the outside from the radio in the jam area, but I'll have to double back along the inside of the seat so there won't be a hump in the carpet and come up right through it. Might not be the prettiest along the sides but I'll figure something out.