[TR] TR3 Differential

[terryrs at comcast.net]

I am in uncharted territory here.  Never dealt with differential issues before.  It's the one thing I didn't go through when I restored the TR3A a dozen years ago.  Car is TS 58667, so according to my manual has the later rear axle (changed at No 13046).  

Toward the end of last driving season, I'd been hearing mild clunking from the rear of the car when starting out from stop. Now looking into it, I have the car on jacks, turned the passenger tire, and got a little play, nothing too serious.  When I pulled the tires, though, and now turn the hub with the car in gear, the driveline does not engage at all.  The wheel spins freely but the pinion shaft does not try to turn.  

Any ideas where to start looking?

Terry Smith,
New Hampshire