What about this? It's the actual part number of the backlit keyboard and this site sells it.
http://mac-pro.com/Merchant2/merchant.mvc?Screen=PROD&Product_Code=pbtikey15b&Category_Code=pp
Replacement Apple Keyboard for PowerBook G4 15" Aluminum- BackLit #922-6105
Quantity in Basket:none
Code: pbtikey15b
Price:$137.77
Shipping Weight: 1.50 pounds
Apple Replacement Keyboard for PowerBook G4 15" aluminum 1.25 Ghz.
Damaged keyboard? Give your PowerBook new life with a new set of keys. Genuine Apple. Part #922-6105. Part Number will not be listed on your keyboard.
For use with All PowerBook G4 15" Aluminum Backlite Models.
New. 6 Month Warranty.
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So I'm just wondering, is it just a matter of the case being able to fit the backlit keyboard better? how much of a difference are we talking? And is it just a matter of putting the keyboard in, OR, is there other hardware requirements to getting the backlit keyboard to work.