How it was actually made....
described here:
https://www.bbc.co.uk/programmes/w3csz4dl
If I remember the descriptions correctly, to save weight some of the metal skin was just 2/1000 of an inch thick!
(part of BBC "13 minutes to the moon" series. I expect that there'll be a bonus episode where they describe designing and assembling the LEGO versions as well :-))