Posi Clunking When I Make Sharp Turns

It's probably not seated the clutch pack yet. I ASSUME it is a clutch pack? Ford was notorious for using the Detroit locker in places you'd never suspect. Are you sure it's not a Detroit unit? That would explain the noise. I've seen quite a few in the 8" units too over the years. Even one in a Pinto with a factory 8". In its defense, it was a V6 4 speed car, but still I consider that mass overkill. If you're sure it's a limited slip (Trac Lok or Traction Lock for Ford) then I simply think it needs more driving.

The figure eight suggestion is a good one. That's how some auto makers recommend breaking in some of these AWD cars after a transmission rebuild. The AWD unit is very similar to a limited slip unit, if it is not the fluid style viscous coupling......or "visious coupling" as we called them when I ran the office at the transmission shop.

Lastly, since the limited slip unit essentially does lock the two rear axles together to some degree, they will never be completely quiet........unless they are broken or worn out.