There are two small bolts holding the straps in on the back. Take those out and pull the strap up and out. It may be stuck in there a bit but you'll get it
Dont forget small bonding strap and wire to level sensor- Heavy if you have lots of fuel in it and it makes it more difficult due to it wants to move on you.
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Keep plugging away it will get done someday
No pain no gain
When you're rich some one will do it for you
It will make you appreciate it more when its all done
Better to be moving and learning than playing video games
The chicks will love it