Hi Dennis,
They run between 16 x 13 and 17 x 20. The more complicated ones, like the ones with wire wheels and extreme reflections take anywhere from 35-50 hours to complete. I use reference pictures that I have taken at car shows etc. I start by composing the picture that I want, car position , background and so on then make a preliminary sketch. I then refine the sketch into a fairly detailed line drawing. If the drawing needs to be enlarged I take it to the local copy shop and have some prints made of several different sizes. I then transfer the copy onto my working paper and start the coloring process. I don't start with any particular area, sometimes the car and sometimes the background. It just depends how the picture is composed.
gbritnell