there used to be kits available that are now NLA. the bracket that connects to the underside of your tiller arm (the two threaded embossments just before the joint) are available used on ebay once in a while, or you can make one, its 0.090" thick stainless. the shift cable connects to the lever on the starboard side of the motor, and the throttle connects to the linkage on the port side of the motor. you do end up taking off the tiller arm and removing the stock throttle cable.
if you want electric start or charging, those parts are NLA as well, and if you look for just the parts, be prepared to pay an arm and leg. you will be best to find a complete 9.8e or 9.8el used. I was lucky to find a 1985 9.8el on craigslist out of Kansas and have it shipped. I am in the process of swapping my short shaft lower over on mine