I'm in the process of essentially rebuilding the feed-dog mechanism of my 153W103, having purchased new parts, now installed, but that await proper adjustment. I'm hoping someone might have input on where to start with with timing of the feed-dog mechanism. This machine suffered what appears to have been a catastrophic failure that resulted in a few broken parts. The hook timing does not appear to have been affected (and that's fairly straightforward). I've replaced the parts, but must