Yup. We did it, BUT to a later model ('79 up have the extra bolt holes that earlier may not) The front crossmember under the rad is stronger too for the skidplate strut/supports for the engine cross bar.
Here's the differences:
Knuckle for 4x4 hub
Upper control arms (unless you want an accidental 3" lift)
Lower control arms
Lower suspension struts (they hang lower than 2wd ones)
Engine crossbar and LH motor mount on motor
Crossbar to rad saddle braces (holes weren't there on my '78 Concord)
Front coil springs are slightly beefier with 6 cyl AC
AFAIK all Eagles use floor shift, but SOTE is column shift because it was 2wd and it was easier to do that with the AW4 we put in (MAX98059 went WAAAY overboard on his cutout. He really only needed a bit on the driver's side of the floor hump for the tcase and front driveshaft)
Rad was bigger in the Eagle.
Swaybar brackets (on the frame) and tierod ends/draglink were all different. Idler shows as same part number 2wd and 4wd.
Steering column needed to be 3" longer due to the dropped down steering box in the Eagle.
Don't recall anything else at the moment. Front subframe is a bit beefed up internally as well but you can't really see it. Car may bend at the firewall without an extra brace for this added
Brake hoses were different too. Early ones used the same calipers as 2wd back to '77ish. '82 and Later ones are same as XJ.