Some questions on the proposed swap and I'll add some info to the Ranger pic above.

What year Ranger did you find?

What engine and trans are in it now?

Have you looked on the web site The Ranger Station or 4BT Swaps?

The Ranger above had the upper portion ( in black ) cut away to place the rad in the support.

Have a look at a 2.3 turbo motor from a T bird, this will give you some sense as to turbo and exhaust clearances ( if the target motor has a turbo )

The Ranger retained some parts through it's entire build from 83 to the end in 12.

Major differences are:

83 to 88 had square glass headlights.

89-90 ( 91 ? ) used plastic headlights / grille from the Explorer

92-97 had rounded fenders , doors that closed into the top of the roof rather than under a rain gutter.

98 - 12 used the 92 doors but the cab and wheelbase grew a few inches in length, front fenders and core support are different than past years.

83 to 97 used twin I beam front suspension with coil springs, you need a lot of room for the front differential to go up and down. Even the 2 WD needs space directly below the oil pan as the beams cross there. 2 and 4 wheel frames are likely interchangeable, I've used a 2 WD radius arm cross member on a 4 without issue.

98 to 12 used a arm front suspension. 2 WD got coil springs , 4 WD for torsion bars, both got rack and pinion steering. The frames are not interchangeable between 2 and 4 WD.

Somewhere in the mid 90's Ranger frames started to rust badly starting with the left rail where the fuel tank is. They also rust off rear spring shackles and frame tails.

There is probably more but that will get you started.