Hi Ed,
I have had a look at McGettigan's and all I could find is that Mr A. McGettigan was trading at Oakfield Place, Cambuslang from 1884 to around 1899. Then Patrick McGettigan traded from Hamilton Road until around 1928.
I then find a Mr M. McGettigan trading as a publisher (National Publishing Co) he lived at 82 Braidfauld Ave, Tollcross.
Edward I am sorry that is all I have, this is because it is not really my field I don't really do provision merchants.
http://www.oldglasgowpubs.co.uk/