So, I've been wanting to add some low end to my stereo system for a while. Car is a 1999 Buick LeSabre so there's a LOT of trunk space. My mids/highs (Polk 6x9s and 5.25s give me crystal clear sound. I need enough bass to compliment, but not overpower, them. I'm figuring at least 1 or 2 10s, but no more than 1 12. I don't want my trunk to rattle like some dumbass - I just want to improve the low frequency response.

Question is, what can I do to hide it all. I don't want people to see an amp and some bright colored subwoofer sticking out like a sore thumb because it just looks corny to me. Looking for something I could sell this car to a 40 year old man still equipped with when the time comes and have him not cringe when he opens the trunk. What (if anything) can accomplish this goal? Do I need to get out a sawzall and start fabricating 8" speaker holes somewhere or can I do something in the trunk?