I went to Inland Empire Driveline for my driveshaft, having been impressed with its easy-to-understand literature, and very concise form explaining how to measure for a driveshaft, which can be filled in and sent to the company, who in turn can fabricate a 'shaft to your precise dimensions. Inland Empire can supply 'shafts in steel, aluminum, or carbon fiber, as well as associated components such as yokes, U-joints, U-bolts, and center bearing supports for two-piece driveshafts. It seems at just over 57 inches my driveshaft is a little on the long side, but not so long that a two-piece 'shaft was advised. Also, thanks to my Classic Performance Products trailing arms, and their pivot points a long way from the rearend, the difference in length from the pinion to the trans tailshaft at the upper and lower limits of suspension travel differed by a mere 5/16 inch, though Inland Empire Driveline offers 'shafts with sliding joints, common among the lowrider fraternity with long travel hydraulic setups and short control arms. For more information on when a two-piece 'shaft is required, check out the tech section on our website (search for Two Piece Driveshaft Technology at www.rodandcustommagazine.com), but long spans, limited space (two-piece 'shafts are generally smaller diameter than one-piece), and smoother running all play their part.