I did my outer with inner to outer. I still have yet to do the inner or kick panels.
http://www.bunchobikes.com/1952suburban19.htm The way I would do it is make the outer fit first. Curves correct, door gaps correct, hood gap correct. Then worry about the inner to outer so you have that back and bottom fender support. Then fit the inner. Some of the mess with the inner can be covered my the mat or rug. All depends on if you are doing a 10 point restoration, a regular car show vehicle, or a daily driver. Personally, I don't care about the inner because I have covered mine with ABS panels. Held in by the windlace and one screw. It even captures and holds my rug in place. Doesn't look like I took any pictures of them, though.
