As yesterday was miserable over here in Lincolnshire I went through the collection of "nope, that's not right" door mirrors.....
The first 2 shots are the car as of now. These work but as they are small by today's standard your view is obviously not as good as on a modern car. As Europa73 has pointed out, they are not symmetrical with the passenger side being slightly angled to get the twist/viewing plane on the mirror. I also modified the passenger mirror by altering the pivot point for the mirror base so it's no longer central and this allows a few more degrees of twist. These are stainless cases and normally come with plain mirrors which I replaced with convex mirrors, again for that extra viewing angle.
The 3rd shows the Vitaloni (?) that came with the car. These mounted on a very short plastic mount, no more than 1/4" deep (which I seem to have lost). This worked fine on the drivers side but completely useless on the passenger side. But they are the coolest looking mirrors.....
The 4th is a Chinese copy, £20 the pair and cheaply made. But these work perfectly on both sides of the car and as they are slightly larger the rearwards view is the best of the mirrors here. The snag for me was that although the mirrors looked ok the pedestal base was too chunky for my tastes and so I didn't bother spraying them to match the car but moved on. But if you want to see behind you, these are pretty much spot on.
The 5th is the Elise S1 mirror, which is a Austin Metro mirror mounted on a Lotus pedestal. I keep looking around for these pedestals because I reckon these would work and look the part on the Europa.
Placing, as others have said, is critical. What I do is set the driver's side first and try to copy the approximate location on the other side to balance it off. I use double sided tape on the door together with some strips hanging from the windscreen to brace the mirror as it dangles roughly in place. A helper would be better !