If no one objects, I'll change the spoken language from Mandarin to Cantonese, as per HKFA

https://ipac.hkfa.lcsd.gov.hk/ipac/cclib/search/showBib.jsp?f=e&id=65537736384005

http://hkmdb.com/db/movies/view.mhtml?id=5995&display_set=eng

You can do it, no problem, but editors must understand 1 thing: almost all the HK and Taiwanese movies (and some PRC movies too) that had international release those days, had Cantonese and Mandarin dubbing at the same time. So, the language is not so important.
The HKFA says "language: Cantonese" because they have the copy with Cantonese dubbing, but there is another copy with Mandarin dubbing of this movie.

ok - i assumed the language choice was for the original language that the film was shot in. You can tell if the audio matches up with their mouth movements or if its a dub. Is that not what we should be looking for?

Not quite. In a movie, actors from HK, Taiwan, PRC, Korea, Japan, etc. usually work together, each one speaking in their own language, and then they are all dubbed in postproduction. A team of Cantonese voice actors dub them to Cantonese, and a team of Mandarin voice actors, do the same thing in Mandarin.

Also, remember that in Mandarin and Cantonese the mouth movements are the same.