I have a 10' awning.  When I finally decided to mount
the leg brackets to the van, I had the same problem
as you--the front leg is over the front door, so where
to put the bracket.

First, I decided to mount the brackets lower than the
recommended range.  That is "so many" inches below the
awning, where "so many" means I don't remember.  That
would have put the front bracket on the front door.

By mounting lower, I could put the front bracket in
the area where a 2wd has the fas filler.  On a Syncro
it is a blank area.  I shimmed the bracket with some
tapered plastic so when I flex the leg back to mate
to it, the angle is right.  It doesn't take much
flexing.

This has worked fine for me for many years.  When the
awning is fully extended, the front door will clear the
leg to open.  Here is a photo that shows the setup:

http://jones.colorado.edu/VW/awning.jpg

Richard Jones
Boulder