I'm sorry. I'm looking and re-ran the video three times but just don't see it.
The sheet of metal from my old chip box was from the bottom of the chip box. Same goes for the new one and I didn't notice any differences in the video. If you find your bottom tray going in under the heat coils, you may have a problem. Make sure it inserts above the coils.
I swear. No parts left over. No extra piece of metal. Have you called customer support? 1-800-489-1581. They have been more than helpful for me.
The extra piece of metal was not on the tray itself, it was part of the smoke box that the tray slides into. If you look at the video at Masterbuilt that shows how to install the tray upgrade you can see as plain as day the sheet of metal that was between the heating element and the chip tray. If you watch the whole video you will notice that the new smoke box does not have that piece of sheet metal between the heating element and the chip tray.
So you don't have to go looking for the link to this video, here it is:
This piece of sheet metal that was between the old chip tray and the heating element prevented the chip tray from getting enough heat to effectively heat the tray enough to always get the chips smoking properly.