by Engineer Spike
Didn't some of the FA/FB units get rebuilt with the capabilities to MU with the '56 roadswitchers, rebuilt RS3, and FL9?
The rebuilt FA's (four of them) could MU with each other or with the GP-9's and other road switchers of this period. They
could also MU with the rebuilt RS-3's. The FL-9's have no means for effecting manual transition on trailing units and thus
if a rebuilt FA was to have MU'd with an FL-9, the FA would have had to lead. I don't recall of any actual occurance of an FA
and FL-9 in MU operation.
Noel Weaver