I just noticed you're in Bedford - I stopped off there for a couple of hours on 24th August, managed to photograph 70013 "Oliver Cromwell" going north with a support coach:
http://daverowland.fotopic.net/p61209656.html
(plus others)
I didn't happen to have a guitar about my person though. Or amplifiers (Marshall 100 combo & 1969-ish Fender Twin Reverb); too heavy to be luggin' around on trains!