Yes, you should list your ingredients as a whole IE "crackers" followed by the ingredient makeup of that component. It is absolutely imperative that all allergens contained within the snack tray be listed on the main ingredient list for the entire product. Here is an example from another snack tray produced by Hormel as to what ingredient breakdown should look like:
"Hormel Pepperoni: Pork, Beef, Salt, Contains 2% or Less of Water, Dextrose, Spices, Lactic Acid Starter Culture, Oleoresin of Paprika, Garlic Powder, Sodium Nitrite, BHA, BHT, Citric Acid.
Sargento Mild Cheddar Cheese: Pasteurized Milk, Cheese Culture, Salt, Enzymes, Annatto (Vegetable Color), Potato Starch and Powdered Cellulose (to Prevent Caking), Natamycin (a Natural Mold Inhibitor).
Butter Crackers: Enriched Flour (Wheat Flour, Niacin, Reduced Iron, Thiamine Mononitrate [Vitamin B1], Riboflavin [Vitamin B2], Folic Acid), Partially Hydrogenated Soybean and/or Cottonseed Oil with TBHQ for Freshness, Sugar, Contains 2% or Less of Salt, Corn Syrup, Leavening (Sodium Bicarbonate, Sodium Acid Pyrophosphate, Monocalcium Phosphate), Butter (Cream, Salt), Soy Lecithin."
This should be followed by an allergen declaration.