1936 Pickup bed floor question

[OldGold360]

Hello,
I am seeking some help regarding the steel bed floor for my '36 pickup. I am in the process of rebuilding the bed and looking at the new steel bed floors that are sold thru Macs. In their illustration of the bed floor it shows two bumps on each side of the panel (see picture). My original bed floor does not have these.

Can someone explain why this is? Is this the wrong bed floor for my pickup?

Thanks

*Bed floor tin did not have the bumps I was originally asking about, but there were some issues with the Mack Hils bed floor tin that I discovered, including misplaced bed mounting holes, and I show how I fixed those issues later in this post. I hope this helps anyone else who has encountered these same issues.