Thanks Danjo, its useful to hear some actual specifics. People tend to always talk in windows/passenger capacity which to me doesn't seem like a very useful indicator when measurements are so much more precise/relevant.
Assuming your are talking about a Thomas cutaway, I'm surprised about the ceiling height, that is quite good, Thomas cutaways always struck me as lower profile compared with collins and bluebird buses.
Do you know what the overall exterior length of your bus is? Do you have a flat floor or wheel wells?