If you use ferrule cement (hot melt glue) to replace the tip top:

1. heat the cement until it's runny.
2. dab some on the rod tip.
3. heat the tip top, not the rod, and instantly slide and position the new tip top on the rod tip.

Heating the tip top will soften both ferrule cement and expoxy for the purpose of removing the old tip top.

Sincerely,

Salmo g.