clicking sound KZ750 Twin 1979

So I am trying my best to put together this 1979 KZ750 Twin but the wiring is killing me.
I think I have most of it now but if I set the bike to run and push the clutch pin in (need to buy a new hand grip) nothing happens. But if I let go of the clutch pin sensor and try to start the engine does not turn over but there is this clicking sound coming from a part next to the battery which I believe is the solenoid? Sounds like a mini machine gun. Also seems like it should only do it when I push the clutch sensor pin in right?

Ideas?

Clutch safety switch might be bypassed inside the headlight shell.

Yes, that's the solenoid, and if it's clicking but nothings happening, then you either have a bad solenoid, bad starter, or bad connection/ground.

Low battery. Tossed the charger on and now she turns over. Thanks!

Yep, the battery had low current capabilty, causing the starter solenoid to "Chatter" when trying to start the engine. Another place to look will be the large battery cables for tightness. Sometimes they develope internal corrosion, actually reducing the conductor size. Flex them, if they feel "Crunchy" replace them, as they are on borrowed time.

Well now I might have a bad solenoid. I got a new battery and tried starting the bike up but after a while (having issues starting it) nothing would happen except a small click in the solenoid every time I try to start the bike.

I am guessing it went bad

So next question. Can I replace the solenoid with any solenoid or does it need to be very specific? I can't seem to find one of this bike anywhere.

Well purchased a solenoid online. For now I am just jumping it with a screwdriver.