So, I ended up adding a copper extension for about 1.5, maybe 1.75 inches. It's just enough to be more comfortable at my perfect driving position. The outer plastic is injection molded around a honeycombed hard plastic center piece that's press fit on using epoxy. I used a heat gun and the hard plastic knob came off with very little fuss. I stepped down my copper bar and grooved the end so that it fit easily into the stock shaft, which is hollow. I threaded three set screws to hold the copper piece firmly in place and thread sealed them with red thread seal. After that I just press fit an aftermarket knob that I had leather wrapped myself. I cut off the end of the set screws and made a leather sleeve to transition from stock to my extension. All in all about three hours of work and it was all done in my driveway with a dremel and a tap set. Not the easiest way to do it, but i really like the result.