That does sound very tempting!
At the link above, click on videos, then scroll down and click on the video entitled "The Original Source Series - The Making of Karajan: Mahler's 6th Symphony.
Karajan Mahler Six
https://dgt.link/karajan-mahler6
I found this fascinating. I particularly enjoyed the separate machine used for the bells. If this link doesn’t open search YouTube for Karajan Mahler 6 Emile Berliner
The YT extract sounded amazing.