When replacing my ignition my key parts fell out.

How can I fix this?

Where are all the springs and top plate that holds them in?

Oh. I see the springs. Where is the top plate?

The longest pin with the round end, goes in the hole that corresponds with the deepest cut on the key. Put the shortest pin with the stepped point up and put any spring on top. Repeat until all pins are in the hole. Put the top plate on and peen the sides on top of the plate. Someone has been into it is why it broke.

There was no top plate on my key housing. That's why all fell out.

I've only worked with the ones with the chrome removeable covers & these might be the same & you need to mix and match the tumblers and the spacers so that the height of a tumbler/spacer combo along with the height on the notch all together lets the "split" where the tumbler meets/contacts the spacer on all (5) of be at the right height (flush with the top of the inside cyl) so the cylinder can rotate/turn in the lock itself. in other words nothing protruding to shallow or to deep that keeps the cyl from turning & each key notch depth & tumbler and spacer heights all combine in height to achieve that. if you lose some parts no big deal as no one picks locks any more (except in the movies) at least in the US of A so (2) functioning holes per lock is fine. what Fastmark said, gotta find or fab the plate & peen it

I made a big score at the locksmith in town when I went in to talk to him about a gun. He does both. I asked about old lock stuff for cars and he had a kit of pins, springs and several styles of covers. All for $17!!! It was an old kit that he had no used for. It's like gold to me. Find a locksmith. They will have the part. If you can't find one. Pm me and I'll send you measurements of the top cover and maybe you can find the right material and make one. I guess worse case, you can send it to me and I'll fix it for free. Shipping costs may be prohibitive.