a body rearend question

Yup, thats all you do. chop and respline. Make sure the B axles are not tapered, ie they are the same thickness where you need to cut and spline. Some have a reduced area that would not be big enough to respline. This reduced area actually gives the axle a little twist like a torsion bar to prevent breaking on a hard shock, straight axles are stronger but are more "brittle" if that makes sense. Lookk at both side by side and make sure the bearing is the same dimension from the hub and then compare cut area to original. should be good to go.