Maybe in the FSM it specifies CCA for the OE battery and you can determine which Odyssey is the right one for you.

With my car, I replaced my hatch struts last summer (RTM) and as soon as you get about 3-4 inches up from the latch, it goes up on it's own and stays up. There isn't any "locking" position that I'm aware of in a 2g.

RTM's were I think $20-$40 for the pair. No brainer! lol