well, a little off subj but I think the solution is to simply buy a clamp on mirror that also has a wider viewing angle. I use the Broadway brand clip on mirrors on my cars, the added viewing angle shows things in the field off axis that OE mirrors can't.

__________________
'95 E320 Wagon my favorite road car. '99 E300D wolf in sheeps body, '87 300D Sportline suspension, '79 300TD w/ 617.952 engine at 367,750 and counting!