Hey guys,
I'd re- think putting heat on those arms. Heat makes a very specific bernd point and it will distort the light sheet metal around the heated area. Mine got tweaked real bad not too long ago, when the arms bend they bend along a really long radius. And mine pushed the windshield back over three inches when it tweaked. In order to fix it, I took the windshield off and bolted it through the hinge holes to the garage wall, just one side at a time, then blocked it at the point nearest to the radius and started cold bending it,moving the blocks toward the windshield top a little at a time. I was only able to take about 1/4 inch of tweak out at a time along the whole arm length, then move to the other side to prevent tweaking the frame in the process. Took a couple hours but it all came out ok, no paint damage, no kinks, a couple broken spot welds but not too bad. You might give it a try before heating it.
Todd