Did a search and didn't find an answer. I broke my 10 bolt gov loc ( finally!! ). Found a 1973 1/2 ton p/u in yard and yanked 12 bolt. Tried some 10 bolt 30 spline shafts (free), were too short by cross shaft in diff. Bought some 12 bolt shafts (told they were) they are too short also. Ended up putting some weld on the end of the axle. My question is will the weld break and axles let c-clips come out? Looks like they might not. I do have another set of supposed 12 bolt shafts coming, just wish I was there to measure them beforehand.