If it is ok to loose the Source page and user note on the caches you can just select the GC codes from one list and add to the other one.
Just select them with the mouse like normal text. Click just before the first code scroll to the bottom and shift click after the last. All gc codes are now selected and a ctrl+c will copy
Switch list and press the + button in the left bottom cordner. Now paste the codes in to the GC-codes: area and press ok. The caches are added to the new list