This looks AWESOME! Great work!
I kinda really wanna do this to one of my KD-58's. I just dunno if I could convince my self to cut the porcelain. My only thoughts were instead of remounting the dispensers, couldn't water from the constant rinse (in my case) be diverted with a valve into a bin like a washing machine so you could fill the soap sections, it would fill the bin and have that drain into the water fill gap or something as it is running?
Basically a rigged detergent dispensing system? All tied into the timer output for the dispenser release? A few relays and a microcontroller would make it simple, just have it sense the dispenser output voltage.
Anywho, this is an awesome project! Love the pics and video!