What's the best way to upgrade '03 tickets?

[Space Mountain Man]

I have 4-day Park Hopper tickets leftover from 2003. Each has two days of credit left. I want to 'upgrade' them (as I did last time) to four day tickets at the beginning of our visit to WDW in three weeks. The tickets I have are (as all were at that time I believe) 'no expiration' tickets.

What credit will I receive for these passes at the ticket windows? I'd like to think they're worth the 2-day ticket price, and I'll simply have to pay the difference between a 2 and 4 day pass. I suspect I'll get something less, but with all the different permutations of tickets available now, it's just to complicated to figure out.

Help!!!

[Beast_fanatic]

If they will accept them as trade-in on new tickets, they will only pay you for what is left on the tickets based on what you paid for them when you bought them. It would likely be best to use them as is and then buy a new 2-day pass.