I don't think a 6 digit pin is going to work. Just have your bank assign you a 4 digit pin, that works just fine in Spain, and everywhere else as far as I know.
DO NOT EVEN THINK OF GETTING TRAVELER'S CHECKS
You do not need them, simply use ATM's when you want money. You get killed with outragious exchange fees when you use traveler's checks, or convert from one currency to another. With the ATM you get the official rate of exchange.
Also, make sure you have a high daily limit on your ATM, so you don't have to take out many installments to get the amount of money you want.
My bank charges me a $2.00 per transaction when I use an ATM that is not Wells Fargo. I expect other banks do the same. So cut down on the number of trips you take to the ATM.
Good luck!