[HELP] Chad Capper's chest key

[jmaverick]

Hi
I've got to find the Chad's chest key. I have a few question.
1. where am I supposed to look for it: only the upper decks of any ship? the spot is randomly generated?
2. how ti make simpler the search: I konw it is possible to change the key into a ladder, how?

 

[shikimikson]

key is on random main deck just on main deck (just first floor on the ship not on ladders),and look around masts more carefully

 

[jmaverick]

key is on random main deck just on main deck (just first floor on the ship not on ladders),and look around masts more carefully

According to a number of sources the key is generated always in only six different places, here they are:
St. Agustine extreme bow
St. Augustine: inclined half ship (base for San Augustune) left side San Augustine, you can get there only swimming
Eva: space towards the bow which contains a piece of bowsprit and a small opening which leads to a catwalk to Esmeralda.
Protector: main deck, next to a vertical metallic object that I do not know
Carolina: main deck, next to a thin board laying on a sort of overthrown table..
Fury:extreme bow
Following these indications I was able to find the key in a few minutes. Mine was on the Eva.
The chest contains many useful things, among them the colored skulls.

 

[Sharks Prize]

What part of the quest am I supposed to look for the key?