Hey Bernard,
The stabilisers on the 3PL attach to the trumpet housings on the each side of the diff. Where they joined the diff does not line up with the bottom pins on the 3PL arms so when you lift the 3PL they become loose and the implement can move from side to side. And it did for me and ripped out the thread and broke the mounting on the housings. I had them welded a couple of times but in the end they broke again and I had to bite the bullet and get new housings. The new ones where a lot stronger and were in line with the 3PL pins so now the problem is solved.
I'll grab some pictures when I get a chance.
As to the flipping I haven't had a problem. I have the tyres 3/4 filled with water and have adjusted the front wheels as wide as they will go and the rear one "notch" less from as wide. Now the wheels are in line and the machine is fairly stable. At present the rear diff lock is locked on and it's due for a service but I still like it.
