Began fabricating a platform to mount the ELT mounting bracket to to the fuselage interior. The instructions for the ELT recommend the mounting bracket not be attached directly to an external skin surface, but it should be installed near the rear of the airplane. So I fabricated a small platform from leftover aluminum sheet and L-angles that will attach to one of the cross ribs aft of the access door and the floor of the fuselage via an added L-angle. Eventually, the mounting bracket and its accompanying straps will be secured to this platform via machine screws.
ELT housing platform - first assembly
ELT housing platform with ELT mounting bracket placed for positioning.
ELT housing platform with bracket, straps, and ELT next to it.