1987 Dodge Dakota Rear

I think some 4/wd Dakota's had the 7-1/4 up front too, but I don't know if that would work if it's designed to be spun in a different direction as the pinion points to the rear when it's mounted up front.

Some A body 7-1/4" had 10" drums with c-clip axles, they had the 4.5" pattern. Look for 73 or 74 and later slant six or 318 disk brake cars. Some got those while others got the 8-1/4".

If you are going to go to the trouble to swap one out you may as well go for a larger axle. You will have to get the driveshaft shortened but it's really not a big deal. You will be glad once you get it done.