There is no enclosure on the non-Shaker systems. I am putting my speakers in today (in about 5 mins) I will take a couple pictures.

 

I replaced my speakers and took some pics if anyone is interested, like he said, in a non-shaker system there is no enclosure. However it is very easy to add the 6x8!

 

Re the front speaker questions: the stock component enclosure depth is 2 1/4" up to 2 1/2" (uneven), but of that only 3/4" sits inside the metal door panel. My 5 1/4" coaxes are much deeper and bigger than the stocks, so I went without the enclosure. From the door panel in is about 2" of usable depth before hitting the window, so I had to use spacers but they fit quite well when finished. From the pic it doesn't look like the coax is mounted flat against the door, but it is (parts of the panel aren't flat, and the camera angle exaggerates it). I was able to get three of the four mounting screws solidly in; they won't go anywhere.