HSK or AP Chinese?

Hey all!

I am interested in a program where I have to concentrate in a language (Upenn huntsman) When I took the HSK 5 four years ago, I barely passed but I still passed. However I am sure I will easily pass HSK 4 and HSK 5 with a bit of study. I have heard that AP Chinese is equivalent to HSK 4, and I want to show the adcom that I already know a bit of chinese. Should i spend a lot of time and get HSK 6, or should i just stick to AP Chinese (self study bc school doesnt offer, will probably take only a month to study)?
Thanks!

For Huntsman, it will literally not matter

One more question - do you think doing either will be necessary for huntsman?

This is what Penn says:

Applicants should demonstrate intermediate proficiency in their target language. The admissions committee considers language coursework taken in high school, language coursework taken outside of high school, language immersion experiences, heritage knowledge of a language, and/or scores on SAT subject tests, AP exams, IB exams, or O-Levels, if available. Applicants to the Huntsman Program also have the opportunity to explain their experience with their target language in the Penn supplement.