Possible Clues:

• Officer getting to the nitty gritty in talk
• Reported grain is rank
• Army three downn
• One has a rank sort of middle, by the sound of it
• End of food chain taking on the Spanish officer?
• Commissioned officer
• A bit of guts shown by the Spanish officer
• Rank (below brigadier)
• Officer I located in Scottish island
• Officer's soft heart, say