Apparently most of the modelers on this board could careless about building a new KW W900. As long as AMT keeps re-issuing the ancient stuff, they will keep buying them. Just a suggestion, why not use your place a KW to try and get a modern KW truck subject as a kit. The photo below is a original Clinf Freeman W900L cab and hood conversion mastered by Bill Drennan, with Revell of Germany sleeper. The cab and hood are now available from P&P Resins. P&P is also suppost to offer a T800 conversion kit.
Also Daniel Gailloux of Plaskit offers a series of modern KW conversions:
http://stores.ebay.com/plaskit