Gakken SX-150 DIY Modular synth ( In progress )

So I have been building my own analog synth out of 3 inexpensive Gakken SX-150 synths. Lots of bending involved. Here's what I have done so far: 500MM softpot added as a control strip for all 3 units. Each unit is tuned by replacing the 75k resistors with