For the VL1 keyboard, turn it upside down, cushioning the keyboard and faceplate areas. The digital circuit board is at the center rear. The two PROM chips are clearly visible next to the lithium battery. Return the backside to the unit, and replace all screws. I powered up and all the led lights flashed a couple of times, and I was then greeted with the 'Version 2' message.
New voices sound great.