Watch the Top Chicks - Top Strings online guitar lesson by Matthieu Brandt from Guitar Lab: Triads and Hendrixian Double Stops
The only thing that changes when you move between triad positions on the neck of the guitar, is the function in the harmony that the triads have. This function can influence their possible extensions, although most of the colors you can add are the same.
Generally you have to be careful around the sus4 shape on the IV chord, because it adds a note to the equation that's not part of the key. Same thing goes for the maj7th and flatted7th sounds.
In this lesson we'll study the third and last position on the top three strings.