Quite honestly I don't know the answer. I think the real answer is more research. This is an entire field within itself, so you better study it up.On the pieces of advice you've received thus far, I disagree with them.The IRS has some smart geeks working for them. Trying to pull "I'm a currency speculator and made millions" isn't going to work at all.The reason is because of the math, specifically the fundamental principal of counting. Currency speculators, on average, get zero profits from their activity. This is true, you can confirm this with any financial expert who is worth his salt. Check the records of currency of commodity speculators and on average they make inflation adjusted gains. i.e. zero real return. Minus the costs of doing the transactions, which technically makes it a negative sum game, something you don't want to be involved in.Now, do you really want to tell the IRS that you suddenly developed an interest in currency trading and made progressively cumulative gains? Forget it. They are simply not that stupid.On the 2nd piece of advice, to keep it in Bitcoin, is just not viable. You want, all your capital, tied up in a volatile instrument like Bitcoin? That's a giant risk.My advice on this, is to get your capital from Bitcoin to a stable currency in cash, or possibly a commodity like gold or silver since they are quite stable in the longer term. Keep it hidden in many separate secret locations.Then, work out how to launder the capital. That's a separate step. You'll need your capital on hand in the form of cash of some type anyway, so you might as well do that first.