Maybe here you can find what you need
http://www.youtube.com/watch?v=245mYSFJdvk i is from the G75 but is more or less the same idea for a G55 did not look at the whole video so it also says how to change your HDD it's very easy to do and otherwise google on it ,and for the fan if you dont have a hobby compressor you can also use a hoover with a soft brush or just use a soft brush to clean.
And maybe other people have more ideas how to and what.
l Asus Rampage 4 Extreme l intel 3930X@ 4800Mhz (1.45volt) 24/7 l Asus matrix GTX 580 l
16GB Team Xtreem DDR3 PC3-20800 2600MHz (11-11-11-28-1) l Coolermaster Silentpro 1000w PSU l Revodrive3 ssd l WD Raptor 150Gb (10000rpm) l Corsair H100 wc with 4 Cougar Vortex fans l CM HAF 932 Avanced case l Acer X243H 24'' l Asus RT N66U Dark Knight l Logitech Z2300 speakers
In progress the custom build PC Samurai Warrior ''Miyamoto Musashi'' in Japanese ''宮本 武蔵'' made by Pascal