After sitting for some time in storage at their Dukinfield Works, gas turbine loco 18100 was converted to an experimental 25kV AC locomotive E1000. Work commenced in January 1958. The conversion of E18100 involved the removal of the gas turbine unit, generator and the middle traction motor from each bogie, which changed the locomotive from a Co-Co to an A1A-A1A wheel arrangement. The necessary electrical equipment such as the transformer, mercury arc rectifiers and pantograph etc. was installed, with the work completed by October 1958.
The loco was later numbered E2001 to bring it in line with the 1957 numbering policy.