This from Erik Haak:

It appears three more CFD Field Chief buggies are marked and ready for service.  Josh Boyajian already reported on 4-5-2 and  4-5-5 back in December.  4-5-1, 6, and 8 were out front of the Tri-Angle Fabrication and Body Company, Inc which is on 43rd Street, just west of Packers.
Photo to Eric Haak
Chicago Fire Department SUV

Erik Haak photo