Does anyone know how to remove the main board on MPC500?

Ok so im trying to remove the main-board but it just wont come out.
I dont want to pull on it too hard and snap and connections or damage the board
I think ive already come close to breaking it

Does anyone know if there's a trick to removing the main board?

Im trying to replace the CF reader.

there are lil clips on the head phone and audio in and out ports on the back, slide them up and off, i was confused too as to why it wouldn't come off after i removed all the screws..lol…its them damn clips

Thanks!! That was it.
Unfortunately I installed the new cf reader and put it back together and tried to format my cf card and it gave me a 'system error!!' Msg.

Now it won't even recognize the card at all.or any of my others. Even if I format them in another Mpc first.

Big waste of time and money. Ah well