Good luck with the project! I've got two 1:6 scale Lincoln Navigator's and an Escalade sitting in storage. I plan to use the caddy as a donor vehicle because it looks cheap compared to the Navigators. After talking with Kenneth about his air setup, I know some of my future mods I just haven't had time to even think about messing with them. If you haven't seen my first Navigator you can check it out here.
http://www.jancecustoms.com/intimigator.html