I don't know which website is good for tewaching you how to unlock as it's kinda easy. Look for the L1 bridges on the processor. See if the 4 bridges are conencted? If they aren't, then they are LOCKED. Find a sharp end pencil to draw the lines to connect them. Careful not to cross connect any of them.
Then look on your board and find if there are any DIP switches. I'm sure you have the A7V and the board mostly come with the DIP switch. Look for it and check the manual for multiplyer settings. You should be setfrom there. Happy O/C!