This is a copy from the tutorial i made on tutorial painting a little while ago, its the steps to do with the lod and the tga to tex, its very simplified i realise
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7. Ok so if you have done all of that and you are happy with how you car looks, i guess you want to get it into the game? Before you do this, i would advice moving the tga file for your livery into the same folder as your lod's for the car, it makes stuff easier. Time to open up GP4Builder, when you do so it will ask you to choose a file to open. Open the lod_0 file that you are using, and your car will appear in the builder, thats a good start. Now go to the tools menu in the top bar, and in that menu there is an option called "Rename Textures", thats the choice you want. A list of all the textures for the car will appear, the one you want is the X1.tga, same as in zmodeler. Double click that one and rename it to X1_templ.tga (or whatever your tga file is called so far), then click apply. This may need to be done to lod_0 for car1 and lod_0 for car2. Now you can close GP4Builder.
8. Final stage! Open up slimtex in ZaZ tools. There is a bar at the top with 4 options. we want the second choice, "Batch to TEX" (its in black). You will have a grid with a few choices at the top like below. You need to drag and drop the tga you've been working on and drop it into the grid. Now click it so its highlighted like in the picture by clicking the name. Now to work on the choices, in the red box the first once is "macro", which you should cars from the menu (2nd option). Now select "prefix" (the blue box) and choose "hi" from the drop-down menu. Its the last one. If you want to choose a specific place for the TEX file your about to make, then click the button on the orange box and choose a folder. Then make sure the box in the purple square is ticked then click convert!
9. Its done. Now all the you need to do is take that tex file you have just created, take the lod's of the car (all 4 or just the lod_0, its your choice), and put them in a wad. There are plenty of tutorials on how to do that
Hope it helps
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