mykeys 10+ year member
URABUS
advise on enclosures I will leave to the pro's i am a back yard builder still learning and not enough experience to help much... but the power cable you are using is far to small for an amp that large.. I think you are going to ned to upgrade that to 2AWG or larger or you could starve your amp or fry the wire (get hot and melt).
Mike
Mike