starter question

Will a starter from a 83 kz 1000 fit on my 83 kz750twin

No. Or at least not without significant modifications (with enough money I guess almost anything can be done). Compare the two in the diagram below and you'll see how different they are. Ed

Is your current starter totally dead? There are cheap rebuild kits available that are pretty easy to do.

I found a starter on ebay it's from a 82 kz750 spectre will that fit on the 83 kz750twin,

No.

You have a Kawasaki KZ750 2 cylinder bike (a twin). You need to ether rebuild the starter you have as Topper recommended or buy a starter for a KZ750 2 cylinder bike (a twin). The KZ750 Spectre is a 4 cylinder motorcycle and it uses a different starter than the KZ750 2 cylinder motorcycles. Below is a list of motorcycles that use the same starter part number. Each one is a KZ750 twin. Ed

KZ750-B1 (1976)
KZ750-B2 (1977)
KZ750-B3 (1978)
KZ750-B4 (1979)
KZ750-G1 (LTD II) (1980)
KZ750-K1 (LTD Belt) (1983)
KZ750-K2 (CANADA ONLY) (1984)
KZ750-M1 (CSR Twin) (1982)

Here is a place that sells remanufactured starters:

www.motorcityreman.com/620-079.html