Hiya 77,
I don't know that amp, so take what I say with a grain of salt.
Speakers hate square waves, which is what happens with a severely over driven amp. Those speaker will really hate it if the square waves are from an over powered amp. So, how the lower wattage speakers will hold up to the higher wattage amp will depend on how judicious you are with the volume control. I say that because you like to play loud. I do too
Like I said, I don't really know anything about that amp, but unless it has modules that require additional wiring, it looks like wiring any other amp to me. RCA inputs are just plug in, of course, speakers are easy and that leaves power, ground and remote, that you connect to remote on the head. Maybe I am missing something with this particular amp. Rule of thumb, if you are not confident, there's a good reason. Either study up or hire it out, as you mentioned.
Why not just use the Xtant to power the 6-1/2" speakers in normal mode stereo and the Jenson for the sub? Skip the bridging and that amp should be pretty well suited for the 6-1/2's. You are going to want the fader feature if you want to hear the back channels. Use the HPF in the head or amp set to about the same as LPF for the sub, and you'll get more sound out of the 6-1/2's, because you won't be amplifying sound those speakers can't effectively reproduce, and those frequencies won't be heating the voice coil. You may find a dead spot between the sub and the main speakers. If that's the case, you can either add another amp channel and a pair of woofs or replace the rear 6-1/2's with woofers. Something that goes well into midrange would be good, then crossover to taste.
Good luck with the adventure!
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