EA SPORTS Rugby kits can be divided into 2 sections. a *.big file that contains a config file (for the collar geometry) and a kit.fsh file (that contains the image file that makes up the kit font). Then there's another *.fsh file that contains all the kit backs.
Tools required for editing...
FshED to export/import graphics to *.fsh files
BIGUI to extract gob files (containing all the game data), export/import files to/from *.big files
And of course some sort of graphics editing package, Adobe Photoshop, GiMP or Paintshop Pro
Don't worry if it seems all complicated at first, you'll get into it real quick
Unfortunately, you'd need to have the game to have all the big and fsh files though. Unless you use two standard files (one *.big file for the kit front and one *.fsh file for the kit back). And work from there, But again you'd need the game to preview your kits as u make progress. So best bet in my opinion is to get a kit template to see what it looks like etc. and wait until you have the game do start editing in full flow
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