The image is for an 'emergency' rear brake line protector... but the November article mentions a front brake line protector. I've read the AMs twice and its using front, front-rear, rear-rear descriptions.
If you have the October and November issues of Army Motors pages 194 and 231
I read this to mean that there is an emergency REAR brake line mod (the angle iron, October AM), a NEW MWO KIT for front (steer axle) brake line protectors for the DUCK/Truck and the November issue of AM details how to convert the Duck/Truck REAR axles as a FIELD MOD. The front brake line kit is never shown, only referenced