How to open engine hatch without power

[Windy City]

I have a 2004 3100 LE Open and the marina who winterized her unhooked the batteries. I found this out after they delivered the boat to my building last week. Now I would like to get the hatch opened (to hook the batteries back up) but of course I have no power.
Is there an override or some other system in place? On a 3100 the batteries are going to be impossible to get to through the small hatch in between the motors.

Thanks in advance for any help