? about custom enclosure

Im planning on doing a custom enclosure in my dodge stealth sometime within the next couple of weeks. I want it to look good, and sound good. Which is the best way to position the subs to get the best sounding bass? i was thinkin of doing it where the subs both angle down towards the center, and have a tilt towards the back of the car. but i wanted to check an see if this is a good setup, or would it sound like crap? right now i have my subs in a box right up against the rear window. but when i had the guys install my system they said thats the only way they could of been put in cuz i would have to remove the spare to get them to face the back of the car. an they said the bass sounds better when faced towards the back of the car. that makes sense, but am curious if it would sound better kinda faced inward at each other. so what is the best way to position them?