I've got a 12' JBL sub in a sub box, in the back of my 86 rx7. I have it just sitting in the back along with the amp. Definetly not to great for it and is for sure easy to steal if someone were to break in. (Alarm system on order hopefully will take care of the theft.)

What ways are there to mount my sub box to the back without getting a big fancy carpet mould?

I was thinking shelf brackets that are shaped like a J. But on second thought i would have to screw screws into the sub box which i dont wanna do at all.

Another idea was to make a wooden frame for the box to sit in, which would be screwed to the trunks body. Would screws harm the hatch?

 

you could also use the bolts that hold down the straps if you need to bolt something down to the car without making new holes...... why don't you want to screw into the box??