Roco’s tooling for its low-nose GP38 model includes a road-specific attribute.  In front of the engineer’s cab next to the nose is a box with two straps.  This is signal equipment control electronics that was a Pennsylvania and later Penn Central feature and not known to have been found on other railroad’s diesels. This release was the final introduction of the mid-1970s Roco-made HO-scale diesels for Atlas.

Chesapeake & Ohio
No. 7064 -1977 release

Detroit, Toledo & Ironton
No. 7065 -1977 release

Grand Trunk Western
No. 7063 -1977 release

Illinois Central Gulf
No. 7062 -1977 release

Penn Central
No. 7066 -1977 release

Union Pacific 
No. 7061 -1977 release

Undecorated
No. 7060 -1977 release