I have one point where I have to cross a 55 mph highway to make a left (at a light).

Unless it is dark when I can see the headlights coming in the mirror, I'll start a 1/4 mile ahead finding a break in traffic (and yeah, I'll slow down too) and just go all the way across to the opposite shoulder. Get to the light and go across like a ped. The safest option for me.