To mirror trouble some bulge maps. ...

• Select which ever bulge map is correct.
• Open the weight painting tools.
• On the weigh paint pallet click [Copy] > copy (Ctrl + C won't work here, use the button)
• Select the other bulge map (The one that's wrong)
• On the weight painting tools select [Copy/Paste] > Paste Mirrored > X Axis (X Is the relevant axis in this case)