To give an accurate answer, the rear is only a semi floating axle. So the axles support the weight of the vehicle somewhat. If it was a full floater I could have just pulled out the axle shafts and removed the rear drive shaft and drove out in front wheel drive. You can't just take out the 3rd member and expect the axle ends to stay put in the center of the housing. Not to mention the gaping hole that would be left in the front of the rear housing collecting everything that kicks up on the trail.
If it happened on the front I would just unlock the hubs and IF I needed to use low range I would also take out the front drive shaft to eliminate the broken gears trying to mesh.
I hope that makes sense. Sorry about the long answers.

 

saw this pic of a recent jeep run on the rubicon, front mounted shackle came apart after dueling with rocks...sure it could happen to any rig,
thought it was kind of cool

 

Most of the jeepers like to swap the shackles to the rear of the front springs for better steering control on road. Also eliminates the beating they take up front.

I'd stay with the Yota axle up front unless you are looking for a wider axle. The Yota front axle weak point is the birfield joints, but its still a pretty stout piece overall.

CB

 

you know that's ironic cuz i have a 1990 4runner sased. 3.4 swap and blew the ring and pinion. (so i thought) further inspection concluded that the ring gear bolts had backed out and believe it or not 4wheel parts are the guys who set up the rear 3rd