So by real bad luck on a gravel road I missed a rock in the road on Sunday (momentarily distracted by kids) - it lodged against the cross bar and road, shearing the 2 mounting bolts clean out of the chassis as well as shearing the mounting rubbers at the case. Speed was very slow about 20km/hr.
Initially I thought I would be leaving with the car on a flat bed but then I noticed some adjacent mounting points (I assume for manual gearbox) which looked like they might work.
So with a 14 socket, the hydraulic wheel jack and rocks as temporary jacks I managed to get one of the mounting bolts to line up. This placed the cross bar at a bit of an angle but still supporting enough of the gearbox to feel confident to carry on. The second bolt I could not get in so hoping for some redundancy in the design we drove home carefully on 3 bolts.
Lessens learnt -
1) Get a transfer case protector (even the thin Mitsu would have probably helped).
2) Always carry tools
3) Always watch the road

4) If the gearbox mounting bolts get ripped out - Mitsu have provided spares - kind of.
5) Never give up
Now we just wait for the damage bill - must say was surprised how thin the steel is at the mounting point - will be interesting to see how it gets repaired. Anyone had a similar problem ?