In 2000 I went to TCI and explained which front clip I had and purchased their Mustang II kit for a 35/40 Ford Air Spring IFS minus the cross member and with the optional power rack.  I paid $1666 for the kit, minus the cross member, and $160 for the power rack. 

Finally in late 2005 I dusted off the pieces and started work.  After I spot welded the frame kit into place and mocked up the front end I found 3 problems.

1) The power rack I purchased didn't appear to fit the mounting holes on the cross member. This is when I discovered the difference between a manual rack and a power rack.  The power rack mounting holes are 15 1/2" apart whereas the manual is 16". Note to others modifying a Mustang II cross member: The entire 1/2" difference is made up entirely on the passenger side.  The left side hole remains in the same location.

2) With the upper control arms at their limit of adjustment, I still had too much camber.  I never determined the root cause of the problem but I suspect the TCI control arms were made for their cross member.

3) The lower control arm mount for the air spring did not seem to line up to the center of the shock tower.

The following pictures detail what at first seemed a pretty scary set of problems that really wound up being nothing.  The guys at TCI were a big help.