That's actually a very good schematic!
In 1988, there were 3 different possible schematics for a GT Mustang, but two were virtually identical, so really there were only two. One was speed density, and the other was mass air. That schematic is for a speed density system. However, for the mass air system, the only difference is eliminating the MAP, and running a line between two open manifold vacuum ports.
Take care,
~Chris