[mikewarot]

A circuit board is essentially a network of connections. If you've got components on it, you'll have to remove them first via desoldering. This process is generally reversible, provided sufficient equipment and training (or luck, in their absense)

You can them use an ohm meter to see what connects to what. Simple, laborious, but effective, and non-destructive. You might want to invest in a milli-ohm meter for serious work.