Take the plastic top plate off with the phillips screws that you see from the top of the truck. Once you get that off, it will slide right out after taking the fuel lines loose. Pretty simple for the most part, and a good time to clean it!

Here ya go. Here is a thread i made that should show you pretty well how it all comes apart.

http://www.rcuniverse.com/forum/m_8406331/tm.htm