Refrigerator cars in Northfork

[NW Mailing List]

Hello
I am rereading the email string from November 2017 about refrigerator cars in Northfork. I am considering reworking my model railroad to include this. Can anyone tell us the cars that would be prototypical and approximate years?  Would the billboard reefers for Swift and Hormel be appropriate?  

My layout uses Y3s and Ms for motive power and I am backdating my car fleet to those appropriate from 1917 to the early forties. 

Thanks in advance. 

Tom Lewis