I want to spin both tires

[yellow70GMC]

a 12 bolt is a semi-floating axle. the axles are held in by c-clips that go on the ends of the axles where they meet the carrier. a full-floating axle has outer hubs, and you can remove the axle shafts without even taking off your wheels or jacking your truck up. in my opinion, a semi-floating 14 bolt is a waste of time, and the extra strength over a 12 bolt isn't enough to make the swap worth it. plus, i don't know how much a semi-floater weighs, but a full floating 14b weighs almost 600 pounds IIRC. I just think a differential swap is wayyyy overkill in your situation unless you ever plan on putting huge tires on your truck. If you're on a budget, just get a lock-right and stick with that for now. They're under 400 bucks. I'm not denying the strength of the 14 bolt, but not everyone needs one, especially high school kids on a budget. Just my .02

amcgeh01-look in 88-95ish "heavy half" chevy trucks. They had 14sf axles. Someone else will probably chime in with the exact years they came in. And i don't think you can limp home on one axle on a semi-floater, just the full floater, which is an 8 lug axle.