RE: Shockwave 55 gel coat and repaint??
You don't need the teflon. Use 5/16" brass and it does really need to be changed to surface drive. Those things had some serious bowsteer with that drive under the hull. That is why they all were changed to a surface drive about 5 years ago.
Cut that whole mess off the bottom and patch it up with fiberglass. Mount the drive with the centerline 9/16" up from bottom and the stuffing tube right out the transom and knock all the bearings out of the strut and run the tube right through it. Get a welded stub cable and a round collet for the engine and you will have a decent driveline and a drivable boat.