Mahagogo - This might be totally off base, but bear with me.... There seems to be a lot of overlap in learning approaches among the severely visual-spatial and the dyslexic (I have both in my house), so perhaps some of the suggested approaches for teaching music to dyslexic children would resonate with you? Most suggest a multi-sensory approach (like Suzuki); we were doing a "Music for Young Children" program with DD which seems to share a lot of those recommended approaches.
Some of the things the program did with rhythm, for example, included having a different sound for each kind of note that took up the correct amount of airtime ("ta" for a quarter, "ti-ti" for eighth, "half note" and "great big whole note"). New and challenging rhythms would be sung using these words, clapped and done with castanets, while also being built of manipulatives on the floor, which you could do in both colour and size differentiation. Body, hand and eyes would move together to sing the pattern while pointing to each kind of (physical) note on the floor. This type of class has a huge emphasis on learning patterns of both rhythms and notes. Patterns are learned as visual pictures (picture a drawing of notes "stepping up vs jumping") and as physical movements. Known patterns are then always highlighted in colour code on the music sheet. Well, I'm sure you get the idea!
This kind of approach helped my DD a lot. But to be honest, her older, crazily-VS brother, would have gone nuts if forced to use the manipulatives and the "full body approach", even though he could have benefitted greatly from the focus on learning, finding and marking the patterns. So YMMV! But just a thought.
