The engine # starts with KZT00, not Z1E, so it is a KZ1000 number. However looking back at the original photograph it appears that the ridge surrounding the boss for the engine # has been sanded off, so it could very likely have been restamped. Whoever did it did a fairly nice job other than the final 0 which is not even visible in the photo.
Former M.E. at Kawasaki Motors Manufacturing, Lincoln, NE
1966 W1 (the Z1 of 1966-50H.P. and 100mph!)
1974 Z1A (disassembled)
1976 KZ900B LTD (SOLD!) it's in GOOD Hands!
1978 KZ1000 LTD
1976 KZ900B LTD pile O parts!