Regarding the connections, I have a standard analog stereo amp with no pre-outs. Just high level speaker outs. So I ran the L speaker high level out to the L sub's L high level IN, then the L high level OUT to the left speaker. Same for the right side using the right high level IN and OUT.
I did purchase a pre-amp crossover unit that's on its' way, a Rolls SX45, which will allow me to use the RCA IN on the subs. I'll use the pre-amps L and R low frequency out to each of the L and R subwoofers for real stereo low frequency output. I assume with this crossover pre-amp I'll disable the sub's crossover and control the crossover cutoff via the SX45.
It does sound amazing right now. But it always does until I find a better way to set them up :P