Delaware Dave, Right ON! Worked first time. Some more details for others.
Indeed midi hl 3 must be set for the midi out of the pedals.
On SK1 go to Edit "drawbars" and unmute them, and it is true the 16' and 8' are the only ones that work once you select pedal button.
You also can assign the bass pedals to separately work for EXTRa Voices too at a different setting, normal, muted, Synth 1, and Synth 2, whatever you like.
I chose a kind of string bass, which you can do by setting the decay parameter and sustain parameters, etc. to your liking. So you can have the pedals work for the Organ manual on one set of parameters and another set of parameters for the EXRA Voices. You also can set it up or down in octaves. But 1 octave down they don't sound good the 16' is now a 32' which you would think is cool, but even with a QSC sub woofer it is not good. Did not try the Pipe Organ sound.
Once you set the channel on the bass pedals, you need to save them to a preset i.e. P01 which I did. And it remains ready to go. Lock the pedals using the Lock switch and your done.
Many thanks Del Dave.....I was going to sell these pedals with my XK-3 I replaced but not anymore. The SK-1 gives them new life.
Hope that helps the group.