Yes, the primer area around the side windows is where the black frame should be. The hood also looks like it might be red primer? Someone was starting to do some paint work on it although I'm not sure what.
It does seem odd the ALL of the exterior trim would be replaced with chrome, so maybe they did sell stripe kits and bezels, but they still would have had to offer a brown stripe kit. I would also argue that the black out trim did not age particularly well, and seems to be generally disliked by many. It is a lot to replace, but it is still plausible that someone special ordered it hat way or switched it out over the years. Notice that the rear bumper is not only chrome but the XLT kind with the rubber inserts.
One thing that does seem reasonable to assume is that Ford must have offered a brown XLS for that stripe kit to exist. Since two have turned up it does seem like a one-off custom repaint.
SHORT BED 4-DOOR DIESEL: 1986 F350 4x4 under construction-- 7.3 IDIT ZF5+GVOD
STRAIGHT SIX 4X4: 1981 F150 2wd to 4x4-- 300 I6 close ratio diesel T19, hydroboost brakes, Saginaw steering
BIG F: 1995 F-Superduty under construction— converting to 6.9L IDI diesel ZF5+DNE2