Wowak installed working valve gear on my Lionel "O" Gauge Reading T-1 (6-18006; 1989). Everything in front of the reverse yoke was missing. He used various parts, including Lionel 700E parts. Maybe he will see this and reply. Or send him an email (address in profile).
Come to think of it, this topic came up a few years ago. Wowak was working on another Lionel T-1. I read about it, corresponded with him, and sent him my T-1. Now she looks great - a big improvement!
Everyone puts the radius rod in the middle of the reverse yoke. That is the neutral position. A radius rod could be moved down a bit to be prototypical. But it would have to be fastened there or supported like the real ones (in front or in back of the reverse yoke). Connection(s) would have to be loose enough to allow the reverse yoke to rock back and forth and the radius rod to move with it.
I vaguely recall reading about this project and even about someone who installed a mechanism to lift both radius rods to the upper part of the reverse yoke when the locomotive backed up. It's possible but it requires precision.
Good luck! Keep us posted!