Hey bud, congrats on your bus. I have a fullsize 1990 bluebird on international chassis. Are you planning a 3 tank setup with onboard filtration or are you just going to have 2 tanks, one for diesel, one for WVO? If just two tanks then you of course wouldn't need to transfer between them because the goal is to keep the fuels separated. In a system with a dirty tank, and a clean tank for WVO you would need to design an adequate filtration system that would be plumbed between the tanks. A few posts below this one in the WVO section, I posted a diagram with my plans on creating this kind of system. It involves the three tanks, with onboard filtration. Sorry I don't know how to link it, but have a look.
From what I've researched, you should use aluminum for any surfaces coming in contact with warm WVO to prevent polymerization, I don't know the chemistry behind this, but it seems to be a common opinion and it isn't too hard to do.
I would definitely add a secondary fuel pump for several reasons. My bus has the 7.3 IDI engine with an integrated stock fuel pump (weak). I hope to never have to replace it because it will cost very much. Secondly, this pump will most likely not pull enough for the added length and viscosity of the WVO. A secondary cheapo pump in an easy to service location will be a great help. Just keep a backup. Or go with a more expensive pump that will last. Remember to regulate your pump to the proper pressure. For me that is something like 10 psi at the injection pump, but this varies widely I believe. My idea was to regulate the pump by diverting excess pressure to the return line and looping it to keep it warm without warming the whole tank. Again, looking at my other post and study the diagram closely.
Lastly, go west and visit everything national park you can. Plan to spend a month.
Edit: Here's the link: http://www.skoolie.net/forum/viewtopic.php?f=16&t=3894