Replacing the battery in my 3 1/2 year old 13'. 

When I removed my old battery, I discovered that the box was not actually attached to the frame. There are two holes in the box that correspond with holes in frame but no bolts. Did someone just miss doing this? There was very minor leakage / venting as there was some white crusting on the frame. The water levels though have never been too low. I never noticed that the box had moved but it's not something I would have focused on. I just installed bolts. Should have done anything different? Seems very odd.