Hello! Thanks the download!

There are plenty of versions for this request, open the "Ver *number*" and take a look at the preview. If you're interested
on it, drag at the "\Steam\steamapps\common\Team Fortress 2\tf\custom\(your custom folder name)\materials\console"

If you don't want to change the gravelpit background, you can rename on it, like on this table:

---Name of the file---=======---What the file contains---

background_2fort_widescreen.vtf <- 2Fort Background
background_gravelpit_widescreen.vtf <- Gravelpit Background
background_mvm_widescreen.vtf <- Mann Vs. Machine Background
background_upward_widescreen.vtf <- Upward Background

--=======---=======---=======---=======---=======---

After you renamed it, place at: 
"\Steam\steamapps\common\Team Fortress 2\tf\custom\(your custom folder name)\materials\console" (same process)

====