Kawasaki Z400J Four Cylinder Part Numbers and seat?

[eNtak]

Hello Everyone been a while... I have now got my hands on a 1981 Kawasaki Z400J2 I believe...either a J2 or J3, one or the other.

What I have brought is pretty much a rolling frame with engine and a set of carbs. The guy I brought it from got a deal of say 5 off them all in varying conditions and me being me picked the roughest one as I like the challenge.

Parts seem to be harder to find for the J variant which is the four cylinder and not the twin. I cant seem to find a manual online to just reference a few things other than Haynes or a used copy for £25-£30 on the bay.

The bike had some seized cylinders, now all unstuck but 1. I feel the piston will break by the time I get it out , engine has been stripped but I'm struggling to find part numbers. Nothing on fowlers and nothing on CMSNL other than the American twin.

I have heard that the wiring diagram is the same as the Z500/KZ500 but unsure on part numbers. I was trying to find a seat but people have them up for £150 plus for ropey ones. I was going to cross reference other Kawasaki models to see what other seats fitting the bike from other models.

This is the same for most other parts.

If anyone could help that would be great!
Thanks