Thanks Michael for the images. I looked at them both. When I look at both images side by side, it becomes obvious in the retouched image that something was cloned/retouched out. The image without the truck is much more pleasing, IMO. Frankly, given the same circumstances, I may have retouched the truck out myself.

Where to draw the line? That is the question the individual photographer needs to ask themselves. In this image, if there had been a whole caravan of trucks, I would have said a reshoot was in order, if the truck had been a fixed part of the landscape, I would have said to live with it, but since the truck was moveable (the driver simply needed to get in and move it) and just a small portion of the image, I would retouch it as well.