Captains:
Gold Coast - Wally Lewis
Penrith - John Cartwright
Also, whilst the RLP match list page lists Phil Gould and 'Buck' Rogers (the assistant) as joint coaches, the Sun Herald match report from the next day states that "Penrith second-rower John Cartwright was thrown into the captain-coach role just hours before the game when Phil Gould decided to stay at home because of an ear infection".
This requires further corroboration from other sources before this can be confirmed - the 'Men In Black' book released in 2008 on the Panthers history is silent on this.