What is the best way to modify Apple keyboards for alternate layouts? I would like to permanently modify my keyboard's button labels to match the non-default keyboard layout that I have set on an Apple computer, so that others who do not touch-type can use the keyboard.  How do I do this?

I have the "Apple Keyboard with Numeric Keypad (English)".

Why?  I don't use the QWERTY layout on my US-bought Apple computer, and Apple does not sell anything except QWERTY keyboards.  This is not a problem for me, as I touch-type, so the labels on the keys are basically unused by me.  But other people (mostly children) use my computer, and I would like to allow them to "hunt-and-peck" with the system-wide keyboard layout.

I have tried using stickers to "relabel" the keys, but this is obviously not very durable and looks terrible and makes it difficult to touch-type since it obscures the little nubs on the "home keys".  Most of the stickers have been worn off.

I am willing to disassemble the keyboard and reassemble it if the keys are physically separate from each other.  But I am not willing to disassemble the keyboard to discover if this is true or not.  I have looked at several Mac "tear down" articles, but none of them illustrate the keyboard mechanism.  If I could simply re-arrange the existing buttons, I would have to remove the "home key" nubs on the "F" and "J" keys and add something to the "U" and "H" keys, but I think I can handle that.

I am also willing to use paint and/or chemicals to modify the labels, but I know nothing about where to start here.  Are the labels painted on?  Or are they a different kind of plastic somehow injected into the button plastic?  Can I paint over the existing labels and then re-paint new ones?  Or would I have to somehow dye the keys to be some single color and then paint on my labels?  What would be a type of paint that is durable enough for a keyboard?

I am not willing to buy a third-party keyboard, unless it is nearly exactly equivalent to the Apple keyboard.  I suppose I am willing to buy a second third-party keyboard and rotate them if that is simple to do with OS X.  But ideally, I want one keyboard with labels that match the default layout, and touch-typers can use whatever layout they want, and hunt-and-peckers can still make do.

Are there any other options?
If you have a keyboard similar to the one described here, it sounds like you can just pop the keys off and push them back down in the new position.