If you have power side mirrors (the type with the stick thing you turn wouldn’t work so well), you can adjust your mirrors to an angle that eliminates (or at least shrinks) your blind spot. Of course this is only the normal driving blind spot, not the crossed eye blind spot, but it can still help. Here’s what to do:
Sitting in the drivers seat, lean your head against the window and adjust the drivers side mirror until you can see down the side of the car, with the car just barely on the inside edge of the mirror. Then lean over into the space between the two front seats and look at the passenger side mirror, and adjust until you see down the side of the car like you just did on the drivers side. Then when you’re sitting straight in the drivers seat you won’t see your own car in the mirrors but you will see other cars going out of your rear-view and into what used to be your blind spot.
Now you have much less blind spot; don’t completely trust that you have no blind spot at all especially with an eye that doesn’t look in every direction it’s supposed to, but this should help a lot otherwise.
Here are some links about this:
How to adjust your mirrors to avoid blind spots This reference from Car and Driver uses helpful graphics to illustrate the mirror adjustments.
Adjusting your mirrors correctly This link from Smart Motorist provides an animated graphic that shows both correct and incorrect mirror adjustments.
Eliminate blind spots If you want more visual explanation and don’t mind the somewhat shaky camera here’s a video.