Nice. If you live in an apartment, make contingency plans for your inevitable eviction. It'll be worth it though.
Properly blending in those subs with your speakers won't be altogether easy since you are using speaker level connections, but it is doable. Like I said before, you will want to plug the ports on your speakers. Make sure you get an airtight seal.
Make sure that the 'crossover' switch is flipped to 'in'.
After that, raise the 'crossover frequency' knob to where the subs bass meets the speaker's bass. You can kind of do this by ear but it helps to have a measuring device like a USB mic. If you do it by ear, use a test tone generator like
this one.
Once the bass from the subs meet the speaker's output, flip the 'phase' switch back a forth between 0 degrees and 180 degrees, and listen for a lowering of loudness at the crossover frequency that you set using a test tone (btw, Hsu may send a disc with sample tracks and test tones in the packing sleeve of the shipping box). Leave the phase switch to whatever sounds the loudest at the crossover frequency. It will probably be 0 degrees, but it doesn't take much effort to check that. once you get the subs phase matched at the crossover frequency, you are set.
All you have to do then is determine how loud you want to run the subs. Again, if you don't have any measurements software, you can do this by ear by just setting the subwoofer's gain level to whatever sound most natural to your ear, however it can be more precisely done with measurement gear and software.