I have a couple of Aura bass shakers on my racing cockpit, I run them with a Dayton 70W subwoofer amplifier.
My limited knowledge tells me that you can't set them up the way you want them. If you're going to use the LFE output on your amp you need a subwoofer amplifier to run the shakers. Four shakers might be too much for 1 amp, though. I would recommend running two 100W amplifiers.
Keep in mind you can always bypass the first amplifier and connect your Xbox directly to the subwoofer amplifiers using Y Rca splitters. If you choose to go with two amps and place the shakers as well as connect everything accordingly (R to one amp and L to another) you can achieve a true stereo shaker setup, which is great for video games. Sounds from your left will shake the left side of your seat and the same for the right side.
Again, I'm a beginner as well, so take my advice with a grain of salt. Hope someone else chimes in and helps you out.