Customer from Hell

So let me tell you a bit about a customer of championwheel.com that lives in a reality beyond my comprehension.   First he asked if 20 inch wheels will fit and says if not he'll take the 18" wheels.  20" wheels show not to fit so I order his them the 18 inch wheels.  The next day after I put the order in he says he wants to go with the 20" wheels.  I tell him the order has already been put in.  He says that is okay he will just return them when he gets them and get the 20 inch wheels.  I point him to my return policy which specifically states that returns on custom wheels are only allowed if there is a defect or the wrong wheel is shipped and inform him that I will charge him a 30% restocking fee plus the shipping costs.  He says okay he'll take teh 18 inch wheels.  The wheels get shipped from the wheel manufacturer and I receive no notification or tracking information from them.  The next day I get a call from the customer saying that they left the wheels on his porch and now they are missing.  I tell him I will notify the manufacturer who shipped them and take care of it.  Next (almost immediately it appears) he calls UPS and gripes them up and down because they left the packages on the front porch in plain view and someone stole them.  A report is filed by the shipper that the items are missing and UPS begins investigating.  I tell the customer that I will replace his wheels when UPS completes their investigation.  He wants the wheels now but not the 18 inch ones he order now he wants 20 inch ones.  I tell him it will be a few days and send him the UPS policy stating so.  He insists that I send the wheels prior to UPS completing their investigation.  I now find out that the packages were shipped with out a signature required which is against my policy.  I call my supplier and he tells me they shipped directly from the factory warehouse and the factory warehouse confirms they sent the shipment without a signature required and that they "always" do this and they "never" have any problems.  They say they will send replacement wheels when UPS completes their investigation.  In the meantime the customer has sent an email stating that he wants 20 inch wheels instead of 18 and he wants me to pay the difference.  I do not respond.  I am waiting to hear from UPS.  The next thing that happens is the customer is calling the shipping company and harassing them for shipping the products with no signature requirement. The he gets back on UPS.  Then UPS tells him about my partner/wholesaler who takes care of my wheel orders and he calls them to harass them.  Then I talk to him and ask him the classic question "what can I do to make him happy" He states (and emails the same) that he doesn't care what I do that it is up to me and I can either overnight him a new set of wheels or give him his money back.  Overnighting the wheels would cost more that all of us together make on the sale so I give him his money back.  All of it, even though I really only should give him 70%.  Next day he rants and raves that I am a liar and that I should give him his money back and overnight him a new set of wheels.  I verify that no one has told him anything that could make me appear to be a liar and at this point let it go.  What a wacko.  I still don't know why he thinks I am a liar. I have no clue why he thinks I am at fault for UPS's mistake.  And I have heard nothing about him filing a police report for the stolen wheels.  As far as I know they are in his garage and he wants me to just send him a new set on faith and absorb a loss of over $1000 because he is a good customer.  Give me a break.  Somebody please tell me what I did wrong.