its funny you mention the flat bar angle, as when we pushed the door closed with the bolts loose that secure the flat bar to the door and nipped the bolts up by hand they sat about 2mm out at the bottom of the flat bar...once I started tightening them up properly it actually pushed the tailgate out further the tighter it got.
@Maysik the hinges are they same as in your pic. I didnt pull them apart at all and slotted them back in exactly as they were.
I have borrowed a tailgate off a mate and im going to try that to see if its my tailgate mounting points....maybe at some stage they were bent or repaired and not done to the correct angle??? anyway ill have to try that and see.
Off to Bathurst tomorrow so ill need to try this tues arvo...
All else failing i might be able to make up a shim to take up that 2mm gap at the bottom of the flatbar and keep it level?
anyway ill keep you posted on developments....
Any more suggestions are welcome!!!!
thanks

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oh and can someone please take a pic of the direction/position of their tailgate rubber seal...when i put mine back on i want to be sure its the right way around.
thanks guys.