Gas Tank Replacement in a New Deck

[sebaugh]

New deck was put in 5+ years ago in my '74 20' CC and now the tank has issues. Question is where to cut up the new deck - entire deck or just where the tank will be?? Hate to do it. Looks like the entire lower (not the forward platform) was replaced right up to the small drain that runs around the side edges. Thoughts anyone. The current tank is only 35 gal - want to make it substantially larger.