Just open Whatsapp with Siseditor and click File list..
I think there is a total OF 57 files..just open each file and rename the installing path from 'C' to 'E' . Now save it.
Unpack whatsapp to any folder
Then check first folder name it C change the C to !
In the unpacked folder.
Now pack it using Sisboom or use any pc tools for packing as sisboom not able to pack files size having 4mb..