Matthew --
My pump is high and back behind my testicles, and was placed there purposely by the surgeon. Since I was single, the Dr suggested that if he put it there my "girlfriends would never find it", though it might be a little harder to access. Both are true.
However, after about a week or two of practice, I had no problem with the location. The pump is below the base of my penis, and the bottom of it well above the bottom of my testicles. Its rests in the middle, but I can easily pull it to one side or the other. Well, more technically, I push my testicles away and pull it a little to the side... there's not a huge amount of give. I'm right handed so I normally access it by reaching underneath and pulling it to the right side to squeeze the pump. However, I can reach it just as easily from the left, but my left hand is not as facile. Or, I can just squeeze from underneath. Pumping and deflating are both pretty easy. I have a Coloplast Titan, not the LGX you have, but I doubt that makes much difference.
Its very comfortable, I never feel it, its never in the way, I have no problem crossing my legs, and it doesn't affect penetration in any way (its behind the testicles, so it doesn't really come into play unless someone would grab my balls from the back... ).
As Bionic_by_AMS says, some surgeons instruct you to pull down to pull the pump into place. However, in my case, the surgeon placed it exactly where he wanted it to end up, and my instructions were to take great care not to move it from position initially while everything healed and scar tissue secured it in place.