The HK contained Holdens first attempt at a V8. Check to see that the weight or power of the engine has not done any damage to the chassis or frame of the car. Also check for front end issues in the steering and suspension, and of course, rust.
Rust in bottom of doors, under front and rear windscreen, in floor pan and in sills
Front suspension issues
Steering issues
Fading/ clouding tail light lenses
Leaks into cabin/ boot
Power options on the higher spec Premier models