In the 1960s and 70s, Nascar had only two class of drivers. The factory backed and the independent drivers. Factory cars made up about 10% of the field with the independents making up the rest. If you could get your car to qualify, you could race. From 1963 to 1980 Frank Warren had 397 Grand National starts and finished in the top twenty 221 times. Limited only by financial backing, Warren proved to be a highly skilled driver and mechanic with tenacious moves on the track.