Polecat has also done a tutorial but that includes this and how to do a complete install. The method used shows how to install walmis F15, Sim-mod A10 and 3GO Su27. If followed correctly will allow for a faultless install with no white models or other glitches.
The tutorial can be found over at http://www.104thphoenix.com/ as the first sticky in the Mods & Tweaks section. You can also download some of the most popular mods including the above mentioned models and the best scenery mods in our download section.
S!