WW, the idea here is to align your subs at the back to meet your comps in front. Hence, with a song you are familliar and have strong kick drum beats, makes this task easier. As the L chanel in front is the furthest away from you(the driver), we takle that channel first.
Once your sub is aligned to your left chanel, you can certainly feel a very strong kick drum response at the T area bottom between dash and center console. Some platforms may require you to treat the T area with sound dampening first before achieving the kick drum effect.
Lastly, u tune the R chanel TA till the vocals(you'll need to use a familliar vocal track for this) meets up with the left chanel in the middle to form a center image. At this point the center image should sound distictively solid with the other musical instruments pan around and behind the vocals. The center image focus, or some say mouth size, big or small, can be further achived by either fine tuning your x-over points or the T/A in 0.1ms intervals.
This method is unorthordox, but after playing with TA for many years, I've found it to be the easiest, in a sense that you do not need to read the Alpine manual.

I suggest you try it, and can provide some feed back.
For active systems, things get a little more complicated.