the problem about a bigger pac file can be bypassed touching ARC file .without new space in ARC only way to have a pac with same bpe size is working on textures..a fool exemple: if bpe is 50 kb and pac is 80 kb , you have to work on textures until you will have a pac less 50..if you do a pac with 40 kb or less then with the HEX editor you can put other 10 kb and you will have a pac same bpe: 50 kb. if textures are worked right your pac will have no problem injecting it with x-packer..and without touching ARC file.