What has worked for me
I have a '94 26 and have had several deck leaks over the years. The best thing I have use is plumber's rope caulking. It feels like play clay and is used to install sink drains. Aply a liberal amount under the track, re-mount it, and with an orange stick (or your finger nail) remove the excess. It will NOT stain the deck, will NOT get hard or crack, and can be easily removed in the future. It can be purchased at any good hardware store.I've found that silicone works well, but leaves a real mess. 3M - 5200 also works really well, but removing it done the road is near impossible.Hope this helps.