Not sure what problems you are having but a steering stabalizer will only mask a problem, not remedy it.
There are two threads that come to mind if you are having wandering issues with your Roadmaster chassis.
Here is a thread discussing the TRW steering gearbox.
http://www.irv2.com/forums/f115/stee...rw-210152.html
Here is one discussing the inherent RR8R chassis design characteristics and the installation of a Watts Link.
http://www.irv2.com/forums/f115/wand...my-124491.html
Lots of excellent reading between the two.
Mike.