I'm trying to get this package of papers ready to mail out tomorrow and would like for it to arrive in HI (from the east coast) Thurs. at the latest. It contains very personal identifying info so I am not comfortable sending it by regular mail, however I don't need a signed confirmation of delivery because I trust the receiving party to email and tell the truth about him getting it. What's the best and least expensive way to mail it? Is that registered or certified? Does that get it there quicker without having to pay enormous overnight fees? It will be a large envelope of papers, if that makes any difference.