The launch of 5th generation F-series for the 1967 model year was going to be big for Ford Motor Co. Ford has seen tremendous growth in sales in the 4th generation and Ford wanted to see that growth continue.
This growth came from buyers that were saw the pickup truck not only a work vehicle but a vehicle that could be used every day as transportation as well a work vehicle. In the 50s and early 60s pickup trucks were work only vehicles for a majority of owners.
Source: Fifth Generation (1967-1972) Ford F-Series: Ford Trucks Go Mainstream