a 15" should work well in there

Agreed^^ And use .75 mdf.

Yeah, That's what sucks about my car. I can't really fit that big of a box in my trunk

Thinking about picking up a blazer or something before spring and just starting over

Do a tahoe or trailblazer....X2 on the tahoe because finding a dual alt bracket from a blazer sucks....

That box is very small for an 18. Like < 4 cubes net.

That trunk is bigger than it looks. In the same body style I got 8 cubes and still had room for 3 amps and two batteries. That was a two piece box though 3 15's sealed in that one