Jim
Yes I did the tinting myself (well, with the aid of the admiral - 2 person job to avoid screwing up those big pcs). I can walk you through details if you decide to take the plunge.
I found the Critical Keys are: plenty of sharp razor blades, a plumb straight edge, a decent squeegy, squeaky clean windows immediately before cutting your pc, soap/water spray mixture (lubrication), handle the film carefully to avoid any wrinkling and don't let it touch ANYTHING between separating it from the backing and placing it on a soapy window, measure 3x and cut once, and TAKE YOUR TIME.
Rushing and beverage breaks before you're done can be a recipe for disaster... I also highly recommend a "no questions" policy signed beforehand by the admiral (or invest in a muzzle)