Cheers!
The amp has the whole boot, when nothing in there!
It runs a 12" kenwood sub that has its box in the boot, but fires through the centre arm rest. The other two channels feed a pair of kenwood 7 x 10s built into their own box above and below the parcel shelf. As this is a fixed rear seat, all is fixed securely to the steel bulkhead, with some holes enlarged.
The head unit runs Infinty 6 x 9s in the front doors and JBL mid/tweets in the dash.