I was having this issue too, when you are customizing the form. Go to Content, in the header check off the box that says Form Name. The word INVOICE will disappear and that will bring that gap together to fit in the envelopes, unlike when manipulating the address and nothing moves. I was even on a share screen with quickbooks and they had no answer. Now if I could figure out how to get statements to fit that would be one less headache.