Tube Yokes typically get damaged when a worn u-joint lets go under load or from getting tweaked using excessive force when replacing universal joints. Replacing Tube Yokes is best done by a qualified driveline shop that can balance the finished assembly, however any competent machinist with a long bed lathe can successfully replace tube yokes. Ford used several diameters of driveshaft tubing for 1959-1979 rear driveshafts depending upon the year, engine, transmission, and wheelbase. Verify your tube inside and outside diameter before ordering! See TM3000 Driveshaft Manual or TSB3510 manuals for driveshaft assembly runout specifications.