How do I set the diffuse shaders 'tiling' and offset values from script?

I’m looking and can’t find anything, best I can do is material.setvector() but not sure how to use it or if it’s even the right hting to use.

If you look in the Inspector for exactly where the tiling is located, you’ll see it’s in the material, which is in the renderer (well, it says MeshRenderer, you just have to know it counts as a renderer.) Then you can look in the scripting reference for Material to see it have shortcuts mainTextureOffset/Scale. So:

transform.renderer.material.mainTextureOffset = new Vector2(0.1f, 0); // +0.1x
transform.renderer.material.mainTextureScale = new Vector2(2, 2);
// NOTE: C#

You can track down the code for most things in Unity this same way.