Boatlife LifeSeal
Boatlife Lifeseal? That's a polyeurathane based sealant with strong adhesive properties... Hummm...
How to remove the Lifeseal... Hummm, I'm not sure... The specfication sheet (see below) on it shows that it's holding power is pretty serious, and provides no resolution for removal. My suggestion is that you contact the manufactuer and ask them about it.
Sorry I cannot be of more assistance. Hopefully some of the others can provide some input and suggestions on removal, etc.
Please do let us know what happens, however - as I would be interested to hear.
//sse