ACER ASPIRE 7720 Touchpad

Unfortently we had a problem the other day where my sister opened bottle of pop over the laptop and it fizzed up and went over the laptop's touchpad and now it's not working
i have went into control panel- mouse- and settings and the laptop doesnt even detect the touchpadd
Now im not sure if you can fix it
if not im going to need to get a replacement
but is this item ok?

http://cgi.ebay.co.uk/Acer-Aspire-7720- ... 2a0fd57900

it says it contains:

Touchpad board with cable

Button board if applicable


So im not sure if that's all i need? to replaceit - anyhow, Im not sure how to replaceit as i took all the screws out around the laptop and removed keyboard then tried lifting the case but it wont lift and i think it will snap if i lift anymore?

So how would i do this? if there's anyone who can help? please. as im not sure what to do
maybe i should buy the replacement and ask a store if they can fix it?
but how much do you think they would charge??

Please help as its urgent!