Transit visa/Temporary Permit (less than 24 hour transit time in Shanghai)

I am a citizen of India and a Permanent Resident (Green Card) of the US. I travel to India via Shanghai in April. I am unclear about the Transit G requirements. Based on my reading, it appears that I don't need a transit G, rather a Temporary Permit that I can apply for at the Immigration Desk in Shanghai. My situation is similar to Marcelina (email thread above) except that I'm a citizen of India.

Any thoughts would be appreciated.
Thanks