Like GRJ stated above, your unit is a working ps2. Why do you need to go PS3 when all you need is the correct BCR.
I understand the PS1 to PS3 but if you have a working PS2, why the urge to upgrade to PS3?
To my understanding, there are no slave boards in PS3. Every unit with motors needs a PS3 board with it. At least that gets rid of the wire teathers?