Another question for Steamer

Basically, you need to set the track carriage to the mark on the main cross bar. That gets the carriage aligned with the sprocket. Then you need to adjust the front idler adjustments so that the ribs are centered on the track chain. To measure that, you'll need to pull off at least one track shoe on each side. If you have the snow shoes, with the oval hole in the center, it's possible to make the measurement without pulling a shoe off.

One thing though, you'll find that this series of machines' manuals build on the earlier ones. I.E. if you're into a 420, you find yourself needing the 40 and M manuals as well. If a topic is covered in the M book, they leave it out of the later ones. The idea seems to be that if you're into this much of a repair, you're a dealer, and have the entire series at hand. Of course, each successive series had changes from the prior one, so there was plenty to print up without duplicating sections that were unchanged.

I mention this only because I've run across others that didn't know this and were missing data in their later manuals (and so many folk read this board) that this might come in handy for someone...