I dont remember a full coach load of Sunderland fans being at an Alty match, but it is possible.
There was a faimily from Sunderland that lived at the top of top of Sandileigh Avenue right opposite the ground, called Robison, there were 6 or 8 kids. They came to Alty in the late 1960's. The three eldest lads reamained Sunderland fanatics. Derek, use to sell programmes with me outside the main stand at Moss Lane in the early 1970's. In the early 70's Sunderland were in the old second division, until they got Promotion under Bob Stokoe. In the late 1970's the Robisons had a lot of relatives that came down for local matches. I remember quite a few of them being in the Moss Hotel one weekend. Bob Stokoe was famed for winning the FA Cup for Sunderland while they were still in the second division in 1973 - and infamous for being the Rochdale Manager when we were cheated out of a League place in 1980.