wire each amp to a different VC on the sub. + to + and - to - as usual. make sure all settings are as close as possible.
the amps have 2 sets of + and - outputs to make wireing easier, they are connected together as basically one big + and - connection block with 2 holes or slots drilled in them.
for the RCA's, take your sub pre out, run you an RCA to the back, then use Y splitters to make 2 L's and 2 R's, and use shorter RCA's to each amp.