The piece om the inner fender is part of an old trailer electric brake control. They were used with a brake controller like this, if needed:
This is a hydraulic actuated electric brake controller made by Kelsey-Hayes and is no longer as it is not compatible with ABS systems.
Bill AKA "LOBO"
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"Getting old is inevitable, growing up is optional"
Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator
Wife's 2011 Flex Limited
Daily Driver 2009 Flex Limited with factory tow package
Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413