Pardon the late response, I always forget to open this window :)

Car skins go in the folders for cars.

Let's say you edited the black trucks skin - pickupnew - then you'd find that at:

State of Decay\Game\objects\vehicles\pickupnew\pickupnew.dds

Same for other files, for other vehicles.

Drop your DDS on top of that and overwrite it, then it will be your new one. As long as you matched the locations of parts, if it was custom, then it should match up with the UV.

Does that help?

the only way ive figured out how to overwrite the dds files is opening the paks with winrar and then placing it in which hasnt worked so far. i saved my dds file as an dtx3 should i switch to 5?

You just save over the old DDS, you shouldn't ever have to dump things in the PAK since the game will pick it up as long as it is in the right directory being pointed to.

oh okay thanks didnt know i had to make the folders

No worries, it's kind of a weird sertup when you look at it abstractly compared to a wide-open setup that one is used to. It's good for the game running, not as easy to mod though :)