TO TURN (or PUT) THE BEST SIDE TO LONDON, verb. phr. (common).To show ones best: cf. HUMPHREYS TOPPERS.
1873. Cassells Magazine, Jan., p. 248, col. 2. This placing the goods in alternate rows of large and small was followed until the top of the box was gained, and then a row of very fine fish indeed crowned the whole. Venturing a remark upon this, the packer grinned as he returned, Allays PUT THE BEST SIDE TO LONDON, govnor. Wouldnt do to shove the big uns underneath. People wouldnt blieve they was there, not if yer swore it. And when we tells em up for sale, we allays picks em up in double rows, takin care to keep the big fish uppermost.