Would anyone know what the reference numbers would be for this watch? The original case back was replaced with a seamaster because of a personalized enscription to my grandfather. Any help would be appreciated in identifying more about it.

 

Why open a second thread on the exact same watch?
In the other one you already got the reply that this is most probably a 198.001.
If you enter this into Google and check the hits, you will find pictures (e.g. on Chrono24) that confirm this.

 

I'm sorry for the second thread, I'm new to the forum and unfamiliar with how it works. I did try the reference number in a Google search and found out more. Once again I apologize for any inconvenience I may have caused and I thank you for the valuable information given here.

 

Agree. Looks like a ref 198.001.

Note there were many different dials used with this reference as well as all steel and gold capped cases.