The 3rd picture in post #5 shows that the anti squeal components take disc brake grease. You would put it on both sides of the slotted piece before install.
If you don't have both pieces, I would get the kit as this keeps the noise down.
I would speculate that your old pads are aftermarket as most only come with a single anti-squeal shim and not the two part that Toyota uses.
If you don't have both pieces, I would get the kit as this keeps the noise down.
I would speculate that your old pads are aftermarket as most only come with a single anti-squeal shim and not the two part that Toyota uses.