When I undertook the restoration of my 4/4 there was only one wing mirror fitted to the car which naturally was fitted on the offside and I was determined to get a matching mirror for the nearside. When I started my quest for the additional mirror I was told they were the same mirrors as fitted to the Rover P6 but not to bother as they were worse than useless. Of course I thought I knew better, thinking they can't be that bad and must be at least functional, but after obtaining the winguard P6 mirror I found out that I wasn't that clever and I discovered that they are OK if you want to look at the sky or obscure parts of the side of your car, but nothing else. So if I was you I would buy a pair of mirrors from John Taylor and some bases from Mr Rutters, not cheap I know, but they look good and they work.