I was reading the letters page in the April 1933 Motor Sport magazine (as you do!!) and came across a letter from a John P Lloyd of Mill Hill N W 7, saying that Scuderia Ferrari were going to run a team of MG Magnettes in the 1934 season.
Autocar had reported in 1932 that the Austin Seven which had been driven by Charles Goodacre in the 1931 Mille Miglia had been entered for the 1932 Mille Miglia by Scuderia Ferrari, but that having "been driven in practice with more brio than discretion" the car failed to make the start due to engine problems.
I have never previously read anything else about Ferrari running (or having the intention to run) small capacity British cars. Can anyone enlighten me further?