I recently found a pristine copy of the official CB350 parts catalog on eBay that covers all the model years from K0 to K4. This is by far the clearest and the most complete parts catalog I have seen. You can look at each parts list and tell the differences between all the model years. The exploded diagrams are also very clear and bear no watermarks. There is also a neat little parts index at the end.
I think a lot of people here would benefit from it greatly and so I scanned and uploaded it. It is a 23 MB PDF file scanned at 150 dpi, for a good balance between clarity and file size.
Here is the link:
https://dl.dropboxusercontent.com/u/418 ... atalog.pdf
Please let me know if you have any trouble downloading the file or if any of the pages are unclear, since I have not gone through each and every page yet.
Update: I have scanned the parts catalog using OCR software, making it really easy to find things. Here is the new link: