Thanks to Ian Ricky for finding and recommending this clip from the film The Jitters (1989), which involves a Chinese Vampire/Jiāngshī Transformation.
I'll let Ian set this up:
"A gang member named Chan (Mark Cheng Ho-nam) was bitten by a Chinese vampire or a Jiāngshī and pronounced dead by his fellow members. Unfortunately, later in the movie he returns from the dead in his Jiāngshī form and start attacking the characters, until he accidentally looks in a mirror and freaks out. The characters uses the reflection to drive Chan back. This causes him to spark and sizzle, melt a bit, and peel away his outer layer and transform into a more powerful, muscular skeletal vampire beast (monster Chan is played by different actor, Joe Podnar).
A bad movie but with good practical effects work, I hope I can found more transformation with this kind of effect, which in my opinion is better than CGI effects."
Agreed, and thanks again!