Wheelbase for the two Bachmann On30 railcars?

[p51]

What's the exact wheelbase for both the rail bus and the railcar (that Galloping Goose looking thing)?
I have an idea of using either to mount a pre-existing body onto it, but I must know first what the wheelbases of each really are to see if either could be used for what I have in mind...

[railexpert]

Hello,

Wheelbase is for

Railcar: 3 1/4"

Railbus 3" exact  2 15/16"


Railexpert

[p51]

Thanks!