How to add a Unit to the A.I.

Could some one pinpoint me to a tutorial or write it up step by step how to add a new unit to the exsisting arsenal of the A.I. generals, so they build and use new units accordingly. Havent tried this part of the editing yet so no clue how to do it, but likely be easier and gonna get it sooner then texturing models

P.S: If its okie with some screenshots added ^^;

Tutorial for Generals.
Tutorial for Zero Hour.