Like Brian alluded to, in all the vast researching I did, I never as any options that allowed for a choice of location of the mounting gear. You get a set of adapters specific to your truck that either the goose or rail mounts attach too. Heck, the instructions for mounting my B&W gooseneck provided a location to drill the 4" hose in the bed to the exact 1/16" of an inch. With carefully doing so, my hitch mounted perfectly in the hole, with absolutely no play either way. Should the hole have been off any more than 1/16", I would have been shaving some off one side to fit the receiver, it is just that exact of a fir.
Maybe there is a brand out there that allows for adjusting, but I never came across it. Custom brackets would certainly have to be built with precision, plus you would want to make certain that whoever manufactured them stood behind their work with a solid warranty.
Like others have said, the only real way to adjust the position of the hitch is to buy one of the ones mentioned that allow movement of the head. The Anderson gooseneck hitch I have either puts the ball 5.5" forward of the gooseneck ball (which is about 1" forward of the axle), or 5.5" to the rear if turned around. I am hoping with my 6.5' box, I can keep it in the forward position, but will have to wait to see.
2017 Escape 5.0 TA (someday soon, I hope
2015 Ford F150 Lariat 3.5L EcoBoost
2009 Escape 19 (previous)
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