Thaw lobster tails, if frozen.
Use kitchen shears or a sharp heavy knife to cut lengthwise through the center of the hard top shells and the meat.
Cut to, but not through, bottom shell.
Spread the halves of tails apart.
Place lobster tails, meat side up, on the unheated rack of a broiler pan.
In a small bowl combine lemon juice and margarine.
Brush mixture over lobster meat.
Broil 4 inches from the heat for 8 to 10 minutes or till nearly done.
Sprinkle with almonds and broil 1 to 2 minutes more or till lobster meat is opaque and almonds are lightly toasted.