I am almost finished with my swing-away lateral head support. In the photo, the support bar looks crooked but when it is bolted down to a flat surface, it is straight up. The bar is held in place by a 1/4" quick-release ball lock pin and to release it to swing away, a lanyard is pulled to drop out the pin. If I can find a good torsion spring, I'll add one (maybe a rat trap spring might work).
Regards, Neil Tucson. AZ