I agree with some of the above comments. The Car Works stuff is wonderful with that Weaver drive but it is pretty tough to find but if you have a full decade to search I am sure you will encounter one. Seems like the last one I saw at a swap meet unpainted was about $450-500? I am working on a Lionel B&O Gp-30 conversion from 3 to 2 rail. Pretty simple conversion all things considered and I will have a great looking, great running model for less than $275. I picked up the Geep on Ebay and wheels from NWSL. I had pieces in my "scrap box" for the pilots and steps and plenty of Scalecraft paint on hand to tie it all together. I am sure the GP-30 was done in 2 rail but I could not beat the price plus I am probably one of the few guys that runs Legacy/TMCC/MTH on 2 rail. Since the Geep was already Odyssey equipped, it was a no brainer.
I had the AC&Y version of the Lionel FM you are looking at but it was way too unlike the prototype to convert so I sold it when I parted with all my 3 rail stuff a couple of years ago. It ran great and looked nice but the trucks, handrail configuration and window areas were NYC rather than ACY so I dumped it.