Here's an example of the files from using
--extract on the v2final-car2-developer.upgrade image:
-rw-r--r-- 1 root root 16777216 Jan 24 17:47 _dev_hda5
-rw-r--r-- 1 root root 475828 Jan 24 17:47 _proc_empeg_kernel
-rw-r--r-- 1 root root 452 Jan 24 17:47 _proc_flash_0c000
-rw-r--r-- 1 root root 1692 Jan 24 17:47 _proc_flash_0e000
-rw-r--r-- 1 root root 327680 Jan 24 17:47 _proc_flash_b0000
_dev_hda5: Linux rev 1.0 ext2 filesystem data
_proc_empeg_kernel: data
_proc_flash_0c000: data
_proc_flash_0e000: data
_proc_flash_b0000: Linux rev 1.0 ext2 filesystem data