depends on if the axle is a good canadate for shortening

some are tapperd down and are not thick enuff to respline

but most truck and c-body axle are good canadates for a re spline

measure the axle to see if it tappers down in the area that the a-body axle will be

29" IIRC

and some truck axles are the 5 on 5.5 wbp also