SP 6000A-6004A
These units were built with alpha suffixes. Over the years, various modifications were done to these units. They were renumbered to SP 6000-6004 in 1949.
SP E7A's - class DP-4 - EMD const. numbers 4152-4154, 4150-4151:
| Original number | 1949 number | notes |
| SP 6000A | SP 6000 | |
| SP 6001A | SP 6001 | |
| SP 6002A | SP 6002 | |
| SP 6003A | SP 6003 | |
| SP 6004A | SP 6004 |