I'm sure this subject has been beaten to death on here, but in my limited experience with templates, I found that they aren't as good as an old fashioned digital photo. While the rough measurements were pretty close, you could find yourself with some things not lining up quite right.
Most of the templates at Sign.com do not go back further than the year 2004. The only site with any significant number of templates is digitaldesignware.com and I am, at this point, totally unsure what their plan is or prices are because they are different every time I go there.
When and if you find what you're looking for, I like many, would strongly recommend to you that you check the template against the vehicle. I recently reviewed some templates and found that the measurements were different just between the different views of the same vehicle in the same template set ... so I only recommend digital photos for this kind of need.