I assume you mean that in 1987 you sold a previous home, bought a home in New Jersey that is still your main home, and postponed the gain on the previous home.
The postponed gain stays with the home that is the "new residence" in Part III of the Form 2119 from 1987. That Form 2119 establishes the basis of the home that you bought in 1987. That will be the basis when you sell that home (possibly plus subsequent improvements). As far as the basis is concerned, it doesn't matter whether it's still your main home when you sell it. You cannot transfer the postponed gain to a different home.
