Home Stretch it is!
After much adjustment of front and rear controls I've got is as linear as I could. A couple notes: the sound is terrible, I have to turn the set up much too loud to hear anything. The video below shows what happens to the picture when I adjust the contrast control. The video starts with the contrast cranked all the way up then some adjusting from all the way up to all the way down a few times.
http://www.youtube.com/watch?v=jVzPM6IlFeE
One other thing I've noticed is that the picture isn't level, it slopes from left to right. Is there an adjustment for that, or is it a symptom of another problem?