La canción del Tunco Maclovio lyrics

Hi, I’m looking for the lyrics of La canción del Tunco Maclovio (from the Alberto Mariscal film with the same name).

I can decypher some bits, but my Spanish is not too good. I would like to record a black metal cover version of this song. Any help would be greatly appreciated!

Rewatching the movie right now for musical inspiration, also did some visual experiments.