1st one is from the early 1960's. Caliber 528-6.
2nd one is more recent. Probably 1980's or early 1990's. Cal. 540.
A fairly reliable method for determining age on these Atmos clocks is to take the serial number, divide it by 20,000, then add to 1954.
For example, if the serial number is 300,000, dividing that by 20,000 would give you 15. Adding 15 to 1954 would give you 1969. That would be the approximate date of manufacture.
An Atmos made before 1954 would need to use a different method.
Hope this helps,