Gary Wallace from GW Trucks makes a nice resin front end correction/conversion for the T600/T800, The front ends of the T600/T800 are completely different from the W900.
The AMT T600A is realy a bizzare kit. It has the T600A hood (flat nose), the T600B cab (sort of) with the single piece windshield, a W900 frame, and a 1970s engine & transmission.