Salsa recipe from Ball canning, called Fresh Salsa. I had never peeled a tomato before. It wasn't as difficult as I feared. Also managed to have enough garden tomatoes I didn't need the backup store tomatoes! 
Yes, boiled for 30~ seconds then into an ice bath then peeled after a bit. It calls for half a cup of vinegar and two tablespoons of lime juice, so that's the acids. And yes, those three would throw off the acidity! I do think I saw a recipe on the Ball website that has corn in it for salsa you might try!