My series 2 4.2 has been dry stored for over 6 years and I whilst it turns over easily and redex has been added to the cylinders I and not sure of the best course of action for preparing to restart. I did not drain the water have have conflicting views on this. On suggestion was that brake fluid can be used to free any rings if they have seized to the pistions.
My plan was to drain the oil, drop the sump and give it a good clean, refit a new filter, prime the carbs (should they be cleaned as well) fir a new battery and give it a go...