Ditto what the previous message said.
You really don't want to be mixing the tweeters and woofers off of different amps. You will have a mess. Not only with impedance levels, but with output levels as well.
The included cross overs produce a balanced system. The amp powering the cross overs sees a 4 ohm load, regardless of whether or not the tweeters are connected.
You're assuming the monsoon cross over amp has the same characteristics as the included alpine cross overs. Not a valid assumption.
You don't say what amp you're using. However, if anything, run the fronts (woofer and tweeters) properly off of the amp.
For the sail panel locations, consider hooking it up with no tweeters (from amp to crossover to woofer).
For the hatch, consider not installing anything back there.
I had the spr-17ls hooked up in this fashion (have the spx-177r in the front), and was quite impressed with the sound output. Ultimately I installed the spx-17MB in the sail panels. Still no hatch speakers.
The way I have my levels set, my sound stage is upfront, but rear fill is present however not overpowering the fronts..
EDIT: PS: Is your discount at bestbuy that good?