Was it not also known as the East Lancs Bypass? I remember travelling down it on the way to the TT in the 70s, and being stuck for hours and hours in torrential rain.
We were in our precious 1950s Riley, on our first trip via Liverpool, and trying to find a transport yard where we had permission to leave the car and cross as foot passengers. We were supposed to follow a route that was guided by three large chimneys in a row, but we could hardly see the chimneys! When we got there, we were so late that the guys had locked the gates. With 10 minutes to spare for the boat, we parked in a lovely space just a hundred yards from the loading area for the ferry. Couldn't believe our luck.
When we came back a week later, in the middle of the night, a fence had been put up around the area, our car was trapped inside and it was a builder's yard for dockside repairs. Took most of the morning to get it back.