So after 200 hours of playing ksp, I still can't seem to land an outpost on the moon. I'm basically building a horizontal "hotdog looking" base complete with all the required components that sits on several landing struts along its length. I have no problem getting it into orbit around the moon, however when I try to land it, the weight balance shifts as the fuel burns up, making it completely un-flyable after about 20 seconds. I've tried everything I can think of. Keeping the fuel in the middle, keeping the fuel on the ends, keeping the engines in the middle/ends, adding a butt load (unit of measurement) of RCS thrusters all over the place, adding an excessive amount of stabilization wheels, but nothing seems to work. The balance is dead center before the decent but due to the different modules all over the base, the balance changes once the fuel starts to drop. I even made a prototype, just using fuel tanks alone without the other modules, to try and make it stable. It sort of worked but again, once the fuel gets to low it might as well be a flying brick.
I feel like I'm missing something obvious. I see all these youtube videos of people landing horizontal bases, and at much higher speeds then what I'm attempting to do. They fly it in like Tom Cruise and set it down effortlessly... probably while drinking a beer with there other hand. What am I doing wrong?