Sun E. thanks. The epoxy comes in small (1 oz) size and is available from industrial suppliers. I got mine at R.S. Hughes. Grainger may also carry it. both brands have a shelf life so check the date.
Unfortunately, with 4 other Hobies I don't have room for a TI. The plug pictured is used on my tandem Oasis -- it makes a great solo machine as well. The plug was installed for better solo speed. As to the shine, I store the boats inside, jealously protect the hulls and use Hobie Protectant to make me think they go faster.
Bosab's experience in heavy seas makes a good case for leaving plenty of drainage in the front cockpit. In my application I've had no such issues, but you could certainly add vent slots as you may find appropriate, or switch plugs in heavy weather. Additionally, it's a good idea to keep the seat scuppers open in the empty cockpit. When running the TI solo (for the TI review), I used packing tape to streamline the front well, but left a slot for drainage. That also worked very well, but was not very easy to switch back and forth.