Yup, and if I don't adjust the axle centerlines into the wheel openings the way I feel it should look I'll be forever bothered by it.

Y'know, with a bit of careful placement, I bet a 108" wheelbase 54 to 58 Dodge pickup could be placed onto a 112" wheelbase Dakota chassis without cutting/modifying the Dakota frame. Plan the front axle centerline under the vintage fenders about 2" further forward, and then remount the vintage rear fenders on the box about 2" further rearward. The running boards would have to be moved rearward about 2" meet up with the leading edge of the rear fenders. Turns a 108" stock wheelbase 54 to 58 into a 112" wheelbase Dakota chassis, done carefully I bet few people would notice.

Or, find a long wheelbase 54 to 58, 116", and mount it on a Gen II or Gen III 112" Dakota chassis. Fudge the front axle centerline forward 2", and remount the running boards/rear fenders 2" further forward and it would match the Dakota 112" wheelbase without changing the frame length. Might have to trim the sidewalls of the box a few inches to move the gate forward to make it look right.

Here are some pics of a stock 55 Ford F1, to me the front axle centerline is too far back in the fender: https://metalworksclassics.com/portfolio-page/1955-ford-f100/

Here are some pics of a stock 56 C3 Dodge, again, even when the front wheels aren't dead straight ahead, too far back: https://classiccars.com/listings/view/915511/1956-dodge-pickup-for-sale-in-arundel-maine-04046

When I mount the 56 on my 2001 Dakota, the chassis will also be lowered as I have a set of 2" lowered A-arms to use with the stock spindles. So when the tires are lower in the fender opening they look much better when the axle centerline is moved forward. To me, when straight ahead, the leading vertical surface of the tire should be about 1" rearward of the frontmost fender opening to look right.