The September 5, 2007 ARRL Contester’s Rate Sheet has the following tip:

To remove stuck-on Coax-Seal from connectors and cables, Carl KM1H recommends Brake Clean if you’re working on the tower. On the ground, use Lacquer Thinner or Acetone which are harder to use aloft. Steve K7LXC also notes that professional grade vapor wraps leave much less residue than Coax-Seal.