This is a late reply, but I just saw your posting. I just restored a 1948 B from the ground up. First, what you need depends on what kind of restoration you intend to do and what shape the tractor is in. A "parade restoration" gets the tractor running with fresh paint. A thorough restoration means going through the whole thing. Two different things altogether.
Second, don't even think about restoration unless you have two genuine John Deere books - a Service Manual and a Parts Catalog. You can get these from John Deere, and they are specific for the year of tractor.Together, you can figure out most rebuilding tasks from the two of them. The parts catalog is not just for finding parts - although you'l need it for that. The exploded diagrams of parts are essential for understanding how everything works.
Third, even with these two books, you'l run into a few things that aren't explained well. That's where the need for magazines and a few key personal contacts comes in. Subscribe to the Two Cylinder magazine and the Green Magazine. They are well worth the subscription cost. You can find everything you need between the two of them, plus lots of interesting articles and tips. Moreover, the Two Cylinder group has technical contacts who volunteer to consult on different types of tractors. The B guy is a great help. I won't give you his name, because he doesn't need dozens of folks calling him who don't support the club. You can find both on the internet. There is a third manual just for the hydraulics, and you may need that as well.
Fourth, essentially all of the parts you will need are available, but they come from everywhere. John Deere still stocks an amazing number of replacement parts for the old 2-cylinders, but not all. You'll find lots of parts in the better salvage yards (the ones advertising in the magazines), and they are usually knowledgeable and helpful. There are lots of aftermarket parts suppliers, and the quality of the stuff is usually OK to good. Beware of aftermarket sheet metal, however. It doesn't always fit well. If you get into replacing bearings, which you will if you want a real restoration, be aware that there are direct replacements for John Deere bearings available from bearing supply houses at usually half the cost of John Deere branded parts. There are cross-references to nearly all of the bearings in your tractor.
Fifth, take photos of every step when you are taking things apart. Make a sequential album. Everything may seem logical when you take it apart, but many months later, the picture won't be so clear. Having your own picture book will help more than you ever suspect when you start out. Besides, it's a fun record of what you've done, and useful proof of restoration to the person you (or your heirs) eventually sell the tractor to.
Finally, although my restoration was a different model year, lots of the information transfers, and I'm glad to offer advice. I'm no expert, but don't hesitate to contact me if you get stuck or have questions. Don't do that, however, unless you've taken the steps above. A decent restoration takes money (more than your tractor will be worth - don't plan on recovering your costs) and lots of effort. You'll get lots of help if you are willing to put in the effort.
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