I think Mark Long Kuan-Wu and Nam Chung-Kwan are the same person.

https://hkmdb.com/db/movies/view.mhtml?id=10546&complete_credits=1&display_set=eng
There is no 龍冠武 in the credits of this movie.


Mark Long Kuan-Wu 龍冠武 https://hkmdb.com/db/people/view.mhtml?id=13792&complete_credits=1&display_set=eng Actor (58 films)
Nam Chung-Kwan 南忠君 https://hkmdb.com/db/people/view.mhtml?id=38746&complete_credits=1&display_set=eng Actor (3 films)

If no one objects I'll merge in 7days.

Merged. Alias ​​has been edited.This time, a BIG5 alias called 鐵國立 was found.