Fluid goes below the rubber bladder, not inside it. There should be no fluid in said bladder, none whatsoever. The bladder acts like a membrane between fluid and air, as you press on the clutch and push fluid out the bladder gets sucked in the master reservoir a bit, then when you release pedal and fluid returns the bladder gets pushed by it back to its original size. You don't absolutely positively need the bladder, you can remove it if you wish, but then as you cycle the clutch humidity from the air will come in contact with the brake fluid that lives in the master and brake fluid will absorb it and degrade over time. Think of the bladder as the rubber membrane on the cap of your brakes master cylinder, it's the same thing only different in shape and size to allow for more fluid/air volume displacement per pedal stroke.
Also yes, a clutch that doesn't release properly will make it a royal pain to go into gear. For comparison purposes I don't have to floor my clutch to shift, by habit 1st and reverse I push all the way down but for 2, 3, and 4 half clutch is all that's needed. NP435 trans, runs the same bell and clutch setup as what your (most likely) T19. Once you have that issue sorted out you can also change your fluid from whatever molasses is in there now to something thinner. Between a buddy of mine and his wife and me we have three 4-speeds all running the Pennzoil Synchromesh fluid and we all think they shift somewhat easier now, both when stone-cold and after running for a while.
