Help me figure out this stability problem

[Analogy]

So I\'m taking advantage of the new .16 'super-engines' and fuel tanks to make a ridiculous heavy lifter based on my old Hercules design from .15. See attached .craft file.

My problem is this: Near the end of the 3rd 'stage,' (i.e. after the first two pairs of boosters have dropped, and the craft is burning fuel from the third pair of boosters) it becomes ridiculously unstable. Starts turning all over the place.

My theory is that as fuel is burned, the center of gravity drops back toward the engines where it is harder for the engines\' thrust vectoring to correct the heading of the vehicle. It doesn\'t crop up on earlier stages because the vehicle is still too heavy for the fuel level in a single booster pair to affect the CG enough for it to become a problem.

Any suggestions? RCS isn\'t powerful enough, if only they had come out with some 'super-RCS' thrusters to go with the super-sized engines and fuel tanks and the increased SCS torque on command modules.

[Analogy]

I\'ve managed to take this thing into orbit one time, when stars managed to align and not knock my vehicle into a spin... Over 200 mass units into a 100x100 orbit. I am very pleased. =D

[Maxed-Rockets]

I like super big rockets, but could you put up a few pictures? You can take screenshots with f1.

[Analogy]

It\'s basically this only with the new larger-sized fuel tanks and engines.

[jersey]

I had the same problem with mine that I just added to the fourm a few topics down, My friend added the AV-R8 winglets and they help a lot with top heavy craft, do them in sets of threes