It's worked (so far) but I don't feel it's a "permanent" solution. I've seen some storage bins advertised on a Harbor Freight e-mail flyer:

I haven't gone to HF yet to physically look at them, but IF the large compartments were long enough to hold the pen kits, I figured I could put the kits in the large compartments and the bushings required for that pen type in one of the small compartments, having a separate container for each pen kit.
Anyone else have any other methods for keeping their parts in order that they'd like to share? I hate re-inventing the wheel.
Thanks in advance.