The suckling pig should, but does not have to, be cured by the butcher. The taste is even better when cured.
Mix the ingredients for the marinade. Brush the pig with it every half hour, only grill the pig for the last 1 to 2 hours to achieve a crispy crust.
For my grill, I calculate 6-7 hours of grilling time for a 25 kg pig. I use 60 - 80 kg of charcoal for this. If you use briquettes, you mix 30 kg of briquettes and 60 kg of charcoal.