Start with removing the steering wheel by prying of the claxon, loosening the big nut and using a puller to remove the steering wheel itself. Some tips to remove the steering wheel without damaging it:
Cut a model out of multiplex or wood that has a hole in the middle with the same diameter as the steering shaft. Fit the model underneath the steering wheel. This will prevent the puller from damaging your steering wheel. Do not completely remove the big nut; loosen it approximately 2 mm above the thread. This will prevent the puller from damaging the thread. Tighten the puller and see the steering wheel come off. Be careful, it is a fit pretty tight fit and the wheel might pop off suddenly: we almost hit the roof!
To continue removing the steering column, loosen the joints that attach the steering column to the front axle. You will need a special puller to do this. By no means use a hammer; this will irreversibly damage the joints! Jack up the front of you and support it underneath the front axle. Loosen the nuts that attach the steering column to the chassis. Carefully lower the steering column, if you still cannot make the angle to completely remove it; jack up the front of your bus a little higher.
Disassemble the steering column and remove the rust using a drill and wire brushes. Use a rust converter to make sure all rust is gone. In my case, there has been a lot of time in between disassembly and rebuild of the steering column. After a few months I was very happy to find all the bits and pieces that belonged to the steering column in marked plastic bags; saved me a lot of time figuring out where everything belonged.
Use a little bit of liquid gasket in between both halves of the steering box, this will keep the paper gasket in place when assembling and will assure leak free operation. Use anti-seize to install the bolts for smooth installation and easy removal in the future.
