[Gary Karr]

I think that if not covered in the RG&JS, you need to imagine how it would have been put together as going down the assembly line. What would be the easiest way for that person to insert a bolt and then put on a lock washer and nut, then tighten it with the wrench he was using. On the early taillamp mentioned above, one would assume that the bolt heads would face out as that looks cleaner. Where on the other hand, it might have been that the nuts and lock washers face out, to the rear as that was the faster way to put it all together as the vehicle moved down the line.