Memory permitting, I recollect taking the down Royal Scot on a Friday in September 1972, departing from London Euston at 10.05 hours, consisting of Mk2a/Mk1 stock hauled by an electric Class 86 Loco. It was a very fast non stop run to Basford Hall but, we then stopped there for several minutes, before entering Crewe for a protracted Engine change to a single Class 50 Diesel. A fast onward journey to just past Weaver Junction then, we encountered several pws slowings/track occupations, passing at least two works trains on adjacent tracks, boldly emblazoned on the vehicle sides on large yellow panels in black type - EUSTON TO GLASGOW ELECTRIFICATION. Beyond Preston via Shap to Carlisle, progress was faster but not spectacular, due to only one Diesel Loco allocated. North of Carlisle, we took the G&SW Route via Kilmarnock and, eventually arrived at Glasgow Central around 40-45 minutes late.
Since it was just a long weekend away with my then girlfriend, the return journey on the Sunday departing at midday took 9 hours to Euston! Albeit, an interesting one, again via the G&SW to Carlisle then, over the Settle Route on via Blackburn and Bolton, where eventually on the outskirts of Manchester, we switched to Electric traction for the remainder.