
to the forums...
Most of the component sets are designed to be mounted within a couple of inches of each other. mounting them further than that would have some unpredictable outcomes. With the power available from your amp for the sub power, the single 10" will probably sound better. The type-R's will play but really prefer more power than what your amp has. Thats why I think the single 10" will use the power you have more effectively.
I like your idea for the 5.25/1" in the rear deck with adapters. I would build something around the rear of them to prevent the sub from moving the 5.25's around (and they will).
Get your mids put in, listen to how much midbass they have, make your decision for the sub from there. As an installer for 16+ years, I can tell you these cars are REALLY built well (meaning a very quiet cab), and dont need as much bass as it will all STAY in the cab rather than leaking out through trunk seals, door seals, etc.
If you have any other questions feel free to ask, I'll do what I can to help...
Bill