The noise out of a pair of 121s on a laden cement or liner was something else too!
There were one or two short stretches around the country where 121s were permitted to run cab first, including the short stretch to Barrack Street at Dundalk...
http://eiretrains.com/Photo_Gallery/Railway%20Stations%20B/Barrack%20Street/IrishRailwayStations.html#Barrack%20Street_20100106_0014_CC.jpg