Weird question about a screw on a ZPA 0.5

[mizatt32]

I took this ZPA 0.5 apart just to check out the heat sink compound because this amp has been sitting for a year and I was putting it back together and I noticed that one of the 9 screws I have pictured has a plastic washer below the metal washer, whereas the other exact 8 screws don't have that plastic washer...just the metal washer. I was wondering what spot that screw would go out of the 9 spots it could go. I didn't notice the plastic washer until I was putting it back together and I was like "dang it, I didn't even notice this plastic washer when I was taking it apart" lol. Is this a big deal? Any help would be appreciated.

PS. Sorry about my bad arrows on the drawings on the pictures lol.

[IsakAlexander]

It were probably located at the spot where there is no mark in the gold trace.

[mizatt32]

It were probably located at the spot where there is no mark in the gold trace.

Yeah I was thinking that as well but they all show signs of having screws put on them.

[IsakAlexander]

Very hard to guess but maybe in a hole where it needs to be above the trace so not to ground it.

[Eric D]

Very hard to guess but maybe in a hole where it needs to be above the trace so not to ground it.

Exactly. Last I remember it was one of the screws in a heatsink section.

[mizatt32]

Very hard to guess but maybe in a hole where it needs to be above the trace so not to ground it.

Exactly. Last I remember it was one of the screws in a heatsink section.

That's also what I was thinking, so it don't get grounded. That's my obvious concern as to why one has a plastic washer below the metal washer and the others just have the metal washer. If you look at my picture and the spot where the orange-ish arrow is where that screw goes (the one in between the red and yellow arrows) it has a built in plastic piece above the hole, that or it was just the washer that stayed on the board when I took it apart. So maybe this amp takes 2 screws that have plastic washers and maybe it's the one directly across from it that takes the other plastic washer (the spot where the blue arrow is).?

Pic showing what I'm explaining. As you can see the plastic piece built onto it or as I said the washer that just stuck on the board when I was taking it apart.

[mizatt32]

I put the screw with the plastic washer in where the blue arrow is in the pic above and I could see a small gold trace that would be touched by the metal washer in this spot which tells me why there is a plastic washer on this screw and this is where it's supposed to be. Hooked it up, works like a champ!