I think its time to start over again. check to make sure that your servo saver isnt giving out or something weird though im sure that you already have.
I would once again suggest my reedy race set up with these changes to it. make sure that you only have 2 or 2.5 deg of rear toe with that set up, and make sure the rear shocks are layed in all the way (i never change that), also instead of 500 rear oil use 400 (XRAY OIL) 40wt other brand oil is not that close. put some fresh tires on the car. 3degs of front camber and 1deg of rear camber.
Make sure to copy it all, if it still dosent steer I dont know. my car would spin out.
with what you were saying before, a stiffer rear spring and really soft front spring will usually make the car push. 2.6R and 3.0F is just the best ballance for rubber tires.
Also if your doing something like putting weight in the front of the car, Take it off. that will make it push worse.
best of luck!
maybe you will just have to send it to me