Requirements:
-Entity (preferably newest)
-Newest MODE plugin
-A lot of time or some 1337 h4x I havent discovered yet
Well first you want to start off by deciding what weapon you would like to edit. For this example I will be using the human sniper rifle.
1.)Locate and open desired weapons MODE tag in meta editor
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2.)Locate the markers section in meta editor and navigate to the chunk that contains the stringid of left_hand or left_hand_(Insert name here)
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3.)Heres what takes the time, change the values under coordinates, ftp the map, and see what it looks like. It's all a matter of guess and check.
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Like I stated earlier this isnt the hardest thing to do, but it's time consuming.
Thanks to:
turk645 for the idea
Xbox7887 for the trainer I took the pictures with
Brok3n Halo for entity
Whoever mapped out that bit of the mode tag