I used Spartite a couple of years ago and the instructions agreed with the comment above. However, Spartite told me they now only want the Vaseline (release agent) applied to the partners, NOT the mast. Therefore, when the mast is unstepped, the Spartite will come out with it, and will be in the proper position when the mast is re-stepped. I complied and sealed both perimeters as instructed, and have never achieved anything close to a water tight seal.
Given the expense, effort (my partners made for a ticky application of Spartite) and the fact that a water tight seal was my main objective, I've been disapointed.