I think you should just try to hook it up without changing anything, on the wiring that is. Remove any TMCC/Legacy equipment from the powered rails for the test. Just test with only the MTH engines getting power. Than add things one at a time while testing. Certain pieces can be a culprit of signal squashing.
I've read posts about it working without major changes. Sometimes you have to physically unplug the Lionel base, or remove the wire. I think that happens more often in 2 rail. You may not have perfect signal and can work to make it better if needed.
I too suggest Barry's book for better understanding of the system's capabilities.
