Hey Rick,
I can't honestly answer because the smallest turnout I use is 064, and that's not in a reverse curve situation. In all probability, you will have problems with 054, even if you make some modifications. I've had problems with 072 and 21" passenger cars.
Most likely your wheels are going to rub on the "ears" of the Kadee mounting box... simple solution, file/grind off the ears. On reverse curves they still may rub and limit the turning radius.
Your couplers most likely will not have enough swing for an 054, especially in a reverse curve. Couple solutions. 1. mount the box further out on the car floor (but probably) won't help. 2. use extended shaft couplers (they will look weird) 3. modify the mounting box and coupler shank to allow for maximum swing. (I did that to all my 21" passenger cars)
Using 054 and extended couplers kind of defeats the purpose of 3RS. I know you like the operational points of Kadees..... but 054 curves just is not goning to be easy or hassle free.
If you're just a loop runner, getting Kadess to go around in a circle isn't too difficult, but if you want to do realistic switching (without touching your cars), slow speed operations pulling and shoving.... go with #4's at least and use the hi-rail wheels. Yes I know people run 2R wheels and I did to for awhile, but once I switched back to hi-rail wheels, with Kadee couplers, I never have derailments when switching.
I'm not going to debate whether or not you can or can't make 2R wheels work, but I will tell you that 054 is going to give you problems switching with Kadees... guaranteed!