In order to adapt the drivetrain to the longer wheelbase I had to increase the length of the driveshaft to match the new extended swingarm. This was actually a rather simple and straight forward process. I simply found some hard steel stock the same diameter as the shaft to use for an extension, cut it to length, and then drilled two 5/16 holes centered in each end. Then using the lathe I reduced the diameter of a central portion of the original driveshaft to a matching 5/16 diameter. I then cut the driveshaft in the center of this reduced diameter portion, and simply slid the reduced diameter sections into the holes at the ends of the extension. Here's a pic: Once in place I welded the three sections together at a very high heat for maximum penetration, with adequate clamping to prevent any warpage. Then I put it back on the lathe, and removed any excess welding material that might of caused to to be out of balance, made sure it was in fact perfectly straight and then installed it the way you would any other drive shaft.