Ah well there you go.
I'm going to replace my piano hinge and see how things line up. For me, I just realized that with the sorry shape of the hinge (it's sagging generally, but is actually starting to break on one side, and has pulled out of 2 or 3 rivets), the latches are probably keeping it from failing completely. So if I have to replace the hinge anyway, I'll see if the latches work afterwards.
If they line up, I'm done! If not, then I'll move on with switching to T-handles.
If it was me, I'd install them the way Bigfoot does. I definitely sat out in front my trailer for awhile looking at what was best, and was definitely worried that if you install them the wrong way, air could easily get up under the cover, release the latch and open on the highway.
Mine are a little different. Same idea though.
Wouldn't want to leave this unsupported.