This is my first post in this forum, and I immediately ask a question helpful in building my model

M48 and M60 have two different types of towers that differ in the shape of the back part. On the M48 and CM-11 models, the rear part is rounded from the ceiling to the base, and for example in M60 Dragon or Magach 7c Academy has a visible edge.
Do the differences result from the type of tank (M48 vs M60) or does it depend on the casting manufacturer?
Regards
Marcin