Required modification of Burner/control system
Carry an extra fuel pump as onboard spare, adjust oil pressure.
Recommendation for burner
Test performance on MGO, adjust F/A ratio, possibly replace oil nozzle with larger model if output is too low. Test flame pick up on MGO and replace non-responding and IR-type flame sensors.
Fuel supply system and change over automation
Where possible substitute DO with MGO and replace booster pump with one compatible with MGO, ensure shut down/by-pass of heating sources by automation upgrade. Alternatively install new MGO line with automatic change over.