Change format of year and volume in apalike2 bibliography style

Change format of year and volume in apalike2 bibliography style

I'm using the apalike2 bibliography style (with some minor customizations that are not related to my questions though.
When I reference an article the format currently looks like this:
Smith, James E.; Nair, Ravi (2005). The Architecture of Virtual Machines. Journal of
Computer, 38(5), pp. 32-38, 2005.
1.) How can I prepend the volume with a descriptor, e.g., "Volume 38(5)"?
The relevant function I have identified in the .bst file is format.vol.num.pages but I didn't figure out how to correctly adapt it.
FUNCTION {format.vol.num.pages}
{ volume field.or.null
  number empty$
    'skip$
    { "(" number * ")" * *
      volume empty$
    { "there's a number but no volume in " cite$ * warning$ }
    'skip$
      if$
    }
  if$
  pages empty$
    'skip$
    { duplicate$ empty$
    { pop$ format.pages }
    { ", pp.~" * pages n.dashify * }    % changed from ":" for vol,pgs -- BJR 10/5/89
      if$
    }
  if$
}
2.) When I have works of the same author in the same year, an entry may look like this:
Microsoft Corporation (2013a). BitLocker Overview. http://technet.microsoft.com/
en-us/library/hh831713.aspx, 2013a.
How can I change the year in the last column so that only the year is displayed, i.e., without the "a"? There seem to be functions output.year.check and format.year.check but again I am stuck with adapting it.
Any help is much appreciated.
Thank you very much in advance