Here is a couple of links of people that had the same issue. It looks like everything has to come out and hold your mouth right.:)
http://forums.mustangandfords.com/mustang-monthly/70/6981350/vintage-mustangs/1972-mustang-convertible-rear-power-window-motor-removal/...
Here is where I downloaded my copy. It has colorized wiring, vacuum diagram, vol 3 of the electrical shop manual, and electrical IPB of the master parts catalog in one CD or download. I find it very handy.
http://fordmanuals.com/estore/scripts/default.asp
Not sure if this what you are looking for but in the master parts catalog in section 120 has all the distributor applications by engine with the part number cross reference.