1967 stang steering wheel

i am a chevy nut working on a friends 67 coupe. has a 289/2bbl automatic. nice condition, hardly any rust. been in his wifes family for years and years. now here's the problem. in texas, they can fail a car's safety inspection if the steering wheel has been replaced with one that is noticeably smaller than original factory equipment. this car has no power steering, and has a much smaller wheel than it should. in short, question is does anyone know the original steering wheel size from the '67's? or know of a place that has these specs listed? thanks in advance for the help.