Sidecar can be found in the NAKED palette while Gridlock hasn't been seen in a while. I do know both are shimmery browns. Off hand I can't recall if I did a dupe using WnW palettes for Sidecar or not.
From
Temptalia's site.
Sidecare and Gridlock are the last two on the bottom row.
I'm pretty sure I did a dupe of Sidecar but will have to look at some of my older posts.
Edit: Ok,
I did do one for NAKED using an old ELF palette (a limited edition item, no longer sold). HOWEVER ELF does have other neutral palettes that will also come close. I no longer buy ELF palettes so I couldn't tell which of the current ones could now dupe Sidecar from the NAKED and BOS palettes.
Urban Decay on top, ELF on bottom.
Left to right: Virgin, Sin, Naked, Sidecar, Buck, Half Baked, Smog, Darkhorse, Toasted, Hustle, Creep, Gunmetal
I do not own Gridlock (least I don't think I do) so I can't do a dupe swatch for it.