There should be another fuse box, under the hood on the driver side fender well, and one under the dash, at least that the way my 2016 e450 ford is setup
If it is the fuse box behind the parking brake than no, it does not come off. Just the cover and you are correct, tough to get at. Some designers, I would like to speak to.
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2014 Sunseeker 3170 DSF
Dorothy, Garrette and Miss Bella.
Retired and having fun.