I did some searching but was unable to find anything definitive. When replacing the battery in our Cherokee I found some corrosion around the drains and am planning to take care of it all. The plan is to remove the battery box, remove the visible corrosion with a plastic putty knife, flush area with water/baking soda to neutralize any acid, flush area, scuff, and then paint/coat the area. My question is it feasible/acceptable to use the Randolph #345 on the areas of the empennage below and around the battery in addition to the battery box or is it more acceptable to just use the Randolph on the battery box and then zinc chromate in the newly cleaned and prepped areas that surround it?