ShortBus,
I might suggest that you'd look at the GVW of the bus and determine if it will fit your needs. I remember driving a Ryder truck, configured the same as your bus, and found that it really felt pretty light in the back. At high speeds (65-75 mph), I felt like the truck was unstable and, to tell you the truth, scared me a little (maybe I was going too fast).
I think I would much prefer dual wheels in the back, but that's my opinion (remember what they say about opnions
).
Robert