Paul,

Looks like your findings are correct. The spring 1920 Electoral Register shows a William Edward Lewis and a Rosina Lewis residing at Ruardean Hill.

Their marriage on 15th July 1911 was at Minchinhampton, both aged 25, fathers named as Leonard Lewis and John Gardiner

I wonder if the Nellie Lewis registered Dec 1917 Westbury on Severn 6a 359 is one of their children