I just bought a (used) Cobra Cat 525. The boat has two under deck hatches running nearly the length of either side of the deck as well as a box hatch on the deck. To my mind the fuel tanks should be in the box hatch and the below deck hatch should be fish hatches. However, the boat has been rigged to take the fuel tanks in the below deck hatches. Any reason for this and how difficult (read costly) would it be to change the setup?