EDIT: Guess I should have read more than just your question. I didn't realize you had it apart already. My bad. Sorry I can't be any help. But maybe my answer will help someone else. Sigh...
http://www.irisvista.com/tech/laptops/Toshiba-Satellite-L355D/laptop-disassembly-1.htm
The L305 and L355 series are pretty much identical except for size.
Yours might be a few months to maybe a year newer than the one shown, but the method of disassembly probably hasn't changed much. I've had my L355 apart 3 times using this guide, and had no problems. As long as you have it apart, it would be a good idea to clean any dust out of the fan and heatsink fins. Good luck! : )
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