Update: as I'm not going to drill anything behind the driver or passenger seat due to that's where the fuel tank location is. It's really the only place I can mount it. It's 14" long by 11" height and 2" depth. It will not fit under the seats. Too long and too tall. I can put it behind the passenger seat. My solution here is to use industrial Velcro stickied onto the back of the amp and the Velcro to the carpet. Tbh it works really quite well and I suppose it's easily accessible.
The seat will go back all the way excluding the last final notch, I think this is fine as I rarely have passengers and if I do, they aren't 6' tall.
So my solution to the behemoth amplifier is behind the passenger seat with Velcro!
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