Roland System 100m

I just got my 181 keyboard in the mail, but have a couple of questions:

How many screws are supposed to be in the end-cheeks? Mine has two on
each side, but it looks like there are supposed to be three on each
side. I opened it up and the extra holes don't go through the wood
like the other two do....

Also, when I turn the keyboard up-side down I hear a 'tinkling' noise.
It sounds like loose springs or maybe the j-wires? Anyone else
experience this or know what I am talking about?

I can't test the 181 yet, as I don't have a power supply set up for
it. Any help would be appreciated. thanks.