Can't empty .GSD files from trash

Hi all,

I have MacBook Air OS X 10.6.8 - copied a buch of .GSD driver files from a PC onto the Mac. Trash won't empty them unless I change the extension - no error message - just won't do it - haven't noticed any other problems with Trash. This is really tedious with over 1000 files - am hoping someone knows a way to configure trash to empty regardless of extension - or - automate changing the extension. Tried dragging them onto a USB stick but only makes a copy - originals remain on the Mac. No problem copying or renaming - just emptying from trash - I'm guessing it thinks they're part of the OS (?)

Thanks much!