Yes, the HT-4 will be running in 2 chnl mode, with each speaker receiving 300W. Rev-8 #1's + on chnl 1 + and #1's - on chnl 2 -. Same with the 2nd Rev-8 using chnl 3's + and chnls 4's -
For the HT-6, it will be running as a 5 chnl: Your sub would be wired bridged on chnls 5/6. For chnls 1 through 4, each will be driving its own XS-650. No in-boats wired together in series or parallel.
Gear needed: 1/0 POS and NEG trunk line, a main circuit protection (i like breakers), a couple of non-fused distribution blocks, some 4 ga from the blocks to the amps for the POS and GND, 2-3 6ft RCA cables. Tower should be pre-wired, but you will need some 14ga to extend from the base of the tower to the amp wall I bet and some for the sub. A few feet of 18ga for the amps turn-on circuit. Terminal ends and heatshrink, etc.