So I've talked a bit here and there about my plans for a couple of years, but here is what I'm working on.
I am taking 3/4" thick MDF pieces and cutting them to fit into flat metal spots on the floor of the trunk, and then I am mounting T nuts from the bottom into those pieces (countersunk so they sit below the surface of the MDF.
I got a big pack of really nice 6 prong T nuts that I'm using.
Then I am sanding the floor of the trunk and using epoxy to adhere these to the floor of the trunk. This gives me mounting points that have real metal threads and I never need to drill into the sheet metal of the car. Peace of mind as well as extremely functional. The other advantage to this plan is that there is 3/4" below the mounting boards that will go in for wires to be routed underneath. Eventually you won't see any wires other than plugging into the equipment.
So onto the pictures.
Here is the bare trunk with the first round of mounting points set and ready to use. The bolts are sitting in them so that I can use them to mark their location on the board that the equipment will be mounted to.
Here is the front and back of the first board going in. On the one side you can see the pencil marks that I used to outline the bolt heads, then I drilled through the center from the bottom of the board. With the board in place I was only able to reach in and half outline the bolts, but that was enough to then finish the outline out of the car. The other side you can see I countersunk the holes so those bolts will lay flush and everything can be mounted over them.
Then here is me sitting the 3 amps in the trunk approximately where they will go. I am orienting them this way so that I can keep all the power and all the signal wires safely away from each other. The empty area to the right in the picture is for all the power to go.
Then I rough built my battery box. It is screwed together for now so that I can take it apart later to carpet it or finish it however I desire. I'll sand the edges and all that to make it look nice then. I have to put a piece over the tap as a hold down strap as well, but I can get to that later, its really secure for now.
The battery box is screwed down and good to go right where it is.
Now that I've shown my progress, I'll lay out the grand scheme. The entire trunk will be covered by this layer of MDF, all the way back. I'll build some hinges in so that the whole thing swings up for spare tire access and then I have some other hardware to use for keeping it all secure when it is sitting in the trunk (more parts-express goodies). I have a sub box half finished already that is build to fit behind the passenger side wheel well and hold 2 JL 8W0s. In the meantime my neighbor gave me some shoddy little box he was going to throw out and I might toss the two subs in there temporarily while I keep working, but we'll see if I bother with that. The rest of the trunk space that I'll have to use will go towards holding all the computer equipment that will someday be running my car entertainment system. That is still a little ways away, but I'm always building for the future. Once all this stuff is in then the computer will actually be pretty easy to install.
After I get that all squared away I'll build the false floor for the trunk. All of that will be buried underneath another floor that will return the trunk to being functional. It will have large plexiglass windows to show off the equipment, and with that will go some lighting inside there. With the final "finishing" phase of the project I'll also build in walls to separate certain equipment that will have grounded metal shielding, carpet or otherwise cover any bare wood, and whatever other dress up I end up going with. There will definitely be a layer of 1/8" hardboard that goes on top of this MDF that will be what gets the final finish, allowing me to go all the way to the trunk walls to meet up with the factory trunk carpet, the sides of which will all go back in and tuck underneath the false floor to give it all a good look. There will also be a pretty advanced cooling system build in with fans, ducting, and baffles.
For now I'm just trying to get everything strapped down and all my speakers powered. I also want to get all the wiring shortened up and the correct lengths to eliminate any excess in the system, especially with the power wiring.