To change the capacitor it is not necessary to lower it, it is not welded, it has some screw caps or connectors, if it is 2 wires it does not have polarity if it is of more wires respect the connection.
Possibly because they were lit they were damaged (part of their magnetic rectitude was damaged), due to overheating:
This is not always the case, if they only burn more, the circuit is not melted, it is closed (in short) and when it melts it is open.