Just to add. I have about 30 project all about the same, all of them reading Falt files into the Warehouse. I go into Windows Explore and copy and paste the complete project.
Then rename the files in Explorer from say File01.Sln to file02.Sln, same for the Dtsx file as well.
Then using a text editor I open all of the new files and search and replace all File01 with File02 and the destination tables.
But, be warned, I've tried this before in 2005 and every now and again I would get errors that the package is corrupt and can be read, but I've never had this problem in 2008 R2.
And I know I should change the GUID's but I still have to do it, just lazy I guess, but all of it works in any case