Like Winston Churchill said, never give up, never give up, never give up. But I will add that with these sleds the long way is the short way - and the best way to have them work satisfactorily is to do as thorough a job as possible.
Early on, because of their simplicity, I had a preference for the intruders. But as time passes I enjoy the invaders more and more. For many years my favorite was the 340, but again with the passing of time I have become more fond of our 440. I wish there was some magic to make them work the first time, however it always seems to be a series of little things. There may be a few frustrating moments, but you are on the right track. These times of frustration are just one more symptom of Mad Kaw Disease. If you look at the number of posts that I have made I will tell you that most were to ask advice about a problem I was having a hard time figuring out. Thank God the guys on this site are patient. Oh, and somewhere on this site I had shared the story of our first Invader - "Free Snowmobile - $2,000."