Probably best to
A) Ditch the ALICE in favor of something that fits (as has been mentioned)
B) Don't feel the need to fill every nook and cranny of a pack!
C) Hit the gym ... honestly, I carried a 60lbs pack over 10 days when I was 15 in Boy Scouts. Are you in that physical condition? I'm not anymore! How heavy IS your pack?
D) post what the heck you're carrying that's so bloody heavy.