Note: There does seem to currently be a bug that doesn't allow you to select the top two mechs in your list. You can change the sort order of your list as a workaround. (default is Alphabetical(ASC))
Edit Note: This method does not seem to work on mechs that you cannot sell, such as Sarah's Jenner, the Phoenix Variants, and I believe the Founder's Mechs.
Edited by Duncan Longwood, 07 February 2014 - 10:44 PM.