Naqshadeynta Class 156 waxay ahayd mid aad uga taxadar badan naqshadeynta hore ee Class 151 ee Metro Cammell.
Dabcan, nooc ka sii adag jumlada ayaa ah "Naqshadeynta Class 156 waxay ka ilaalin jirtay naqshadeynta hore ee Class 151 ee Metro Cammell, jirka jirka waxaa laga sameeyay bir halkii laga samayn lahaa Aluminium, iyo naqshadeynta qolka ayaa si ula kac ah ula mid ahayd BREL Class 150 si loo fududeeyo aqbalaadda ururka. "