Paul Broderick for me, although he only retired in 2001. Mark Chaffey I thought was tough too. I was pretty young when those two guys played the most of their football, but I remember them being my favourites.
Otherwise strongly agree with Staff (loved how he dropped the knees in), Hilton (brave), Coughlan (real pity), Bowden (always going back with the flight), Kellaway brothers, oh and of course Richo although he wasn't a dirty/imposing player IMO he was very brave/tough.