The Travelling Post Office Help

[GWR-Kris]

Im looking at making a travelling post office train, my layout is set in early 2000s and wanted to put together a train. Now having checked there is only currently two era 9 post office coaches 374-980 and 374-980A. All the others appear to be ERA8. However 374-975 and 374-975A appear to be very close in terms of the livery.

Does anyone have any info to help put together a rake ideally looking for around 6 coaches atm

[crewearpley40]

Ideally

1 BG Gangway Brake
2 POT Stowage Vans
3 POS Sorting Vans

374975 abd 980 are designated POT

Looking at 374901 / 2


Are you modelling any particular area / region as some formations were short and later
became longer trains egoriginated Plymouth travelling to Scotland?