KZ400 Fuel Tank Compatibly

Can someone point me to or have a resource on fuel tank compatibly. I just purchased a 78 Kz400 and It needs a new gas tank. I don't see any for sale here recently, and ebay ones are really rusty or quite expensive. I think I need to expand my search to see what other years will fit. If anyone has any insight please help!

I had to purchase a tank for my KZ400 and was able to find a clean one in the right color on ebay for $50 or so. Don't be too worried about the rust issue, If it is solid and it is just the inside of the tank that is rusty you can achieve amazing results with a battery charger and some rust remover. I took an old XS650 tank that was very rusty inside but fine otherwise and made it look like new.

Try comparing tanks at Partzilla or Kawasaki.com. At least some rust is to be expected.
A 70s KZ400 with the same method of attachment would be the best fit.
The 78 B1 has a tab & damper, so I would get the same type. KZ400 B1, C1, B2. Others?
The 80 KZ440-B tank appears to be very similar, so maybe??? Red dented
You could check the later 440 models to see if there are any others, but I think they are different.

With a non-stock tank the front mounts may not line up right or the tank might not clear the frame or the length could be off or have a different rear mount or something.

Some models attach at the rear with a bolt or a band/strap, so adapting one of those would take some work. I have no idea how hard it would be, but it might be doable, assuming that one of those fits the frame otherwise.

Thank you for the help!