ilasm utility has a /resource option that allows one to specify a resource with version info.
Here's an example of the new command that sets file version for the generated (re-assembled) DLL:
ilasm.exe Interop.filename.il /dll /key=snkey.snk /resource:Interop.filename.res
MSDN documentation for ilasm.exe can be found here:
http://msdn.microsoft.com/en-us/library/496e4ekx(v=vs.110).aspx