There are a few examples of combining an FFR kit and a "Mr Bruce" body.
However that seems to involve building the kit yourself, perhaps some fabrication skills and quite a bit of time.
Here is an example of an 8 year build of an FFR/Mr Bruce FIA body:
Factory Five 289FIA Build
Of course CSX 2049 did not have an FIA body.
Here is an example of an FFR/Mr Bruce slab side body build:
The first Factory Five slabside
I wonder if Mr Bruce would consider offering a roller, but that does not seem to be his business model.