The nashorn can see through only 1 hex. That means you can ignore the obstruction, whatever it is(forest, city, mountain, etc). If the enemy is behind 2 hexes of obstruction, then it is no good.
SS-Jagpanzer Extended Range 12
Jagpanzer (1944) Ext. Range 12
Jagdpanzer IV L/70 No ext. range
Jagdpanzer IV/48 (1944) No ext. range
Jagdpanzer 38 T (Hetzer) No ext. range
STUG III G No ext. range
STUG III D No ext. range