Replacing a Passat battery?

My 2002 Passat is now over five years old and I still have the original battery. I would apprecaite help with two questions;

(1) How do I take off the engine panel to determine if the battery acid level is low?

(2) The dealer wants $78 to install a new battery. Is it necessary to go back to the dealer or can I simply have Sears install one of their international "Die Hards" for a $12.99 instllation fee. I realize the dealers are always more. However, I am concerend if any part of the computer system needs to be "rebooted" because of the electrical system being disconnected.

Thanks

remove rubber trim around the plastic and "pull off" clips. Its very easy. To fit back its the reverse.

You supposed to use a battery back up system when you chang e the battery in most passat's. it keeps the computer alive.