> And the average pickup is probably shrinking right now, not growing - for example, there are fewer and fewer models with 8" beds, and 5.5" is the new standard (instead of 6").

For non-Americans: While literally writing truck bed lengths being 8 inches (8") and 5.5 inches (5.5"), the text means 8 feet (8', 2.44m) and 5.5 feet (5.5', 1.68m). Americans don't always remember which of the " and ' is which, so they use these interchangeably (and according to the movie This is Spinal Tap, so do the English).