For thouse of you wondering how to make the VCF CV IN mod it's the same pin in VR2 where the moog slayer mod take place, just put a diode, for example an 1N4148 between the positive CV and VR2, ground the negative CV, keep the voltages between -5 and +5 V and you are good to go. Using Expert Sleepers Silent Way I get aditional LFOs in sync and with multiple waveforms as modulation sources for the VCF, including S&H.
I don't have wiring picts but you can see how my Poly 800 II looks like here: