Those links would indeed move the axle rearward. An issue could arise with the axle making contact with the fuel tank upon upward travel though. You'd just have to see how close the diff is to hitting the tank beforehand while the suspension is compressed to gauge how far back you could move it. Replacing only the upper link with a longer option will lift the pinion to lessen the angle of the driveshaft and slightly move the axle rearward. That should remove the need for a lengthened driveshaft and give a slightly better axle placement at ride height without switching out the lower arms. I think that twist might tweak the panhard bar a bit however... it would probly still work tho. Consider also the more you move the axle to the rear the further back it is when it flexes into the wheelwell.
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