JBL 1200.1 on 15 L7

I have a JBL 1200.1 and I am getting a 15 L7.  I want to know should I get the 2 ohm or 4 ohm.  And could u guys tell me why I should get it.  And also how should i wire the sub to my amp.  I am going for spl.  If I like what i hear I probably will get another L7 but that will be months from now.  But what is the best choice for me as of right now.  Aslo how deep should the box be.  This guy who owns a shop had his L5 in a box that was only about 14 to 16 inches deep or wide however u look at it .  OK facing the opening to the back.  Is this good how deep should it be.  Help me out guys. 

I would get a dual 4 ohm voice coil speakers. I would wire the voice coil in parallel for a 2 ohm load. If I had a second one I would run the v.c.'s in parallel as well as the speakers in parallel. This should give the amp a 1 ohm load which I think your amp is stable to one ohm. I would add a fan to cool your amp if you are going to drive a 1 ohm load because it will be hot. As far as the box size you should go to www.kicker.com and get a data sheet on the sub. That should give you the appropriate box size, port length, and all other info you would need.