Sorry, I'd been confused about whether I could access objects on a drawer directly from the class that controls the parent window. I literally could not find any information anywhere about whether it worked that way.
Ended up putting together a mockup and figuring it out. I keep forgetting that if you can't figure out how to do something in Cocoa, you just have to stop thinking about it and try the easiest way it could work. doh!
thanks,
-N