Sorry to be such a pedant Ian, but that Arsenal match was two seasons earlier in 68/69. In 69/70, we were drawn at Fourth Division York City in the Third Round and needed an own goal by their captain Barry Swallow to draw 1-1. I it was the same score in the replay at Ninian Park and then they beat us 3-1 at St. Andrews I think it was in the Second Replay. I only saw the match down here, but I can remember reading after we were beaten that York were the better team in all three of the matches.
So, the Brentford game was the second consecutive year that Scoular's team that spent three seasons in the promotion hunt and beat Real Madrid on the back of a run to the Semi Finals of the Cup Winner's Cup in 67/68 came a cropper to a team from the basement in the FA Cup - my main memory of that Brentford game was that, like yesterday, it pissed down for most of the match. Back then, I thought City played to their max in every game, but it seems that, just like today, some matches were higher priority than others.