Before anything else, thanks for installing the template you guys
So
rickyreter, you know how editing and saving the images from the PSDs work? Anyway, just in case...
So first, edit the header part using the provided PSD
For saving the modifications, cut the modified part by means of "Crop Tool" and "View>Show>Guides". Then save the respective image over the old one in the "Images" directory (For this template... Cars\Upload\cars\images) In "File" menu, select "Save For Web".
When you get to finish that, upload the whole images folder again.
Hope this helps