Ok lets pics some brains here. I've known for some time now but just didn't really look into it. UP had three FEFs with triple stacks. 835, 837 and 839. They remained that way till they were retired.
Can anyone shed some light on the reason for triple stacks and if it made a difference then the twin stacks. I have three Kato FEF type. I made a grayhound of one not knowing they were gonna do it two years later and the other I will do the triple stack thing just to be different.
Thank you,