I have a NP208 with the slip yoke and have been looking for a way to get rid of it. I found a website driveshaftsuperstore.com, that sells a "flange" that looks like it slides over the factory output shaft in the slipyoke and on the other end is the flange with predrilled holes for a cv driveshaft or others. But it says to drill and tap a hole in the center of the existing output shaft to bolt the flange in place. Is this okay or will it weakin the shaft????? If not it looks like a good idea. I know it wouldn't allow me to add alot of length to my driveshaft but I could get one with more joints.