"It's like Aberdeen on a flag day..."

My late Grandad, a Scot, loved watching films and had a good memory for quoting lines.

The way our family remember him telling it, this one was from an old war film. A tank is crossing the desert, probably in North Africa, and the commander opens the hatch to check if the enemy is within sight. He looks around, but there is nothing apart from sand in every direction, so he says, "It's like Aberdeen on a flag day." One of us believes they saw this film a long time ago, and that Rex Harrison said the line.

I've done some searching but can't seem to find references to this film on the internet. Have we misremembered it, or does this ring a bell for anyone?