The time to load up my w200 with more fuel has come. I've already got the in-cab tank (anyone have some clues about the amount this tank holds?) and I'm looking at getting a second tank for under the bed. Anyone know what sort of size I can stuff under there? Can I get a 35 gallon RC tank under her? Either way, I need to start looking for a selector valve. The cheapest I've found thus far is a ford unit from the old ford 250's that came with the dual tanks. Aside from that, I've found one for like 60 bucks. Anyone got any other leads?