Alligator gar get amorous down in the Mississippi River Delta in May and do their thing in the shallows - where I once fly fished for redfish. Spotted a tail once, fishing from a canoe, passed a popper to its owner, got bit, and stuck one between five and six feet long. It freaked out and almost capsized me as it ran beneath the canoe - not much room for it there! Anyway, at the time I was well aware that redfish tails were pointed and gar's were rounded. I guess I just had a slight mental lapse.
I have, though, taken them to 20 pounds or thereabouts while fishing for deep specks with Clouser-types. Neat stuff - they often give you one really good jump.
Good luck with 'em.
Pete