Ya id go ahead and try it, I had an amp attached to the back of an older stang. It was just plywood on the trunk side underneath that carpet. Use screws that aren't too long of course and when your done do a quick check and feel for them on the other side of the seat.
i am just about to do the same thing with a JL Audio JX250/1 mono amp. I checked under the carpeting through the hole for the latch at the top of the seat and it looks and feels like plastic to me. I will mount the amp and all related wiring to a 11x18 in amp rack built from ˝ inch MDF and use four 1 inch number 10 screws to mount the assembly to the back of driver side rear back seat, pre-drill holes first.
Canadian 2012 V6, MT, Perf.White Pony Package (3.31 gears). Koni Sport Shocks & Struts. Steeda Sport Springs w/HD Mounts, Route 66 SpeedShop 55D rear spring kit. Boss 302 Strut Tower Brace. BMR Adj PHB. BFG G-Force Sport Comp2. Pioneer TS-D6802R Front SPeakers, Clarion 80W/Ch Amp. JL Audio 8 Inch Sub And 175W Amp. GT500 Steering Wheel. 2012+ Tilting Headrests