Rear seat platform

[DerrickC9035]

Hey guys I'm new to the installation and building process of car audio always had a system just never installed anything myself anyway I have never been to a show before or seen a big system other than on YouTube sooo I don't have any idea how to do what I need to give you guys a rundown of what is going on I decided about a year ago to get into competitive audio and started learning how to do everything from the front of the car to the back I just finished my power supply (240 amp autotech, autotech VCM, double run of 0 gauge OFC to the back feeding a 29AH SCIB bank from NORTHWEST LITHIUM charging at 15.8 ) I drive a 2019 Toyota Camry LE and I was trying to do a trunk build with a D4S HD3 single 15 enclosure and a 15" Incriminator audio TYRANT rated for 5K RMS to put on my new AAK 6k with D4S 6x9 and 6x5 for the doors and the AAK 180.4 for the mids and highs with a mart's digital BTX8 BT DSP I have never ran anything bigger than the CXA 1800.1 that was in my trunk up until last week so I have made a major upgrade anyway I received everything this week and went to install it and the enclosure won't fit in the opening of the trunk so I'm trying to build a platform in place of my rear seat and just slide the box in and bolt it to the platform im eventually going to order another Tyrant 15 and build a 4th or 6th in the rear seat area and put a 10k on each lol 😂 baby steps though I just want to use the 700$ enclosure for now can anyone tell me how to go about building the platform/floor where my rear seat is im stumped on how to start and get it to actually hold and be stable enough for my crazy driving and strong enough to hold the 300+ pound enclosure and sub my gas tank is located beneath the rear seat so welding and drilling are out of the question and I refuse to pay anybody else to do it I want to learn how myself like I have everything else so far 

[Big Tex db]

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