the rear doesn't need tweeters. the sound is meant to be coming from the front, that's why people put components at the front. If you've already bought the alpine components ffor the rear (is that what's in the pic?) then juts don't connect the tweeters. that way you're not hearing any high frequencies from behind you.
as foir the Bose being able to handle it, it's the other way round. the speakers need to handle the Bose. and they will they're designed to work with an amp so they'll handle more power then you'll be giving them.