there are four possible battery options for my old bus ,
61Ah /330A
72Ah / 380A
80Ah / 380A
95Ah / 450A
but since the one fitted at the moment doesn't match any of those trying to workout which one is the actual one that would have been fitted is becoming a tad difficult.
I think best bet now would be to go with a 80Ah/380A as its middle of the road , just checked ECP and they do one with the same spec as the 80Ah battery listed by audi for £90 ish pounds and with this weekends 35% off that's down to £59.00, I 'll give it a go and see what happens.