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Having spent hours and hours removing my fuek tank I now have a new one from Tim Fry landrovers. It won't go in though. Keep gettin git to within about an inch, but no luck. It's a 1990 Defender 90 Diesel. Any ideas?

I bought some nut splitters. They worked, but seized in the middle so I now have only one bolt to remove, and a broken set of bolt splitters. Trip to Screwfix later to complain! I also got a dremel and tried to grind - it wasn't helpful, and the cutting discs couldn't get in at the right angle :-(

I'm trying to undertake the very simple task of removing my fuel tank off my 1990 Defender 90. My small problem is that the heads nuts and bolts at the rear mount are all rounded off leaving me no way to remove them. The front mount bolt sheared when I tried tried to undo it, but at least it's off. Have tried hacksaw blade with tape around it, but unfortunately the blade is too thick to fit in the gap. Anyone got any ideas?