I have never had a good explanation provided for the question of why ALL (existing) FEC pacifics have 95-100% flexible bolts in the side sheets. There must be a reason...there is a reason for everything, regardless of wether or not it is based on logic is another story.

Jason - somewhwere in my boxes of stuff I have an old green envelope containing photos of FEC steam in the scrap line which shows some interesting variations is the flexible staybolt patterns. I bought it back in the '70s at a train show in Miami.

dave