I have found the Review of Army Tank Program 1969, which mostly talks about Sheridan problems but also M60A1E1/E2 (M60A2) and MBT-70:
https://books.google.com/books/abou... MBT-70 meant to replace all US tanks&f=false
It really shows how inept program management caused these disasters to happen. Congressmen seriously imply that officers managing Sheridan ignored test results showing problems with the combustible case and pushed for Standardization and production of the vehicle even as no conventional ammo was available, and even the ammo fielded in Vietnam had a 20-page long list of limitations and warnings when using them. They did it to keep funding.
The US wasted some 1.5 billion dollars (MBT-70 cost 303 million at the same time when coop with Germany ceased) to produce some 1.5k M551s that were stored until 1970-71 and were never brought to the kinda reliable state of the M551A1s.
M60A1E1 and E2 production was also authorized 6 months before even 10% of the testing was done, testing which went slowly because the things were deadlined 76% of the time.
You can imagine that if such inept management existed for those vehicles then it's likely it explains the M114 disaster or the tank cupola fuckups.
Now please save me from this neverending nightmare by butterflying this cursed 60's decade of American AFVs...