John and Robert.
The LaBelle F&CC coach is a very different animal from the D&RGW coach.
Yes, it is longer. The D&RGW coaches were mostly Jackson and Sharp, though they did have others as well. Those coaches are what the LaBelle kit is based on. Basically the same model as the Blackstone cars. The F&CC coaches were built by Billmeyer (sp?) and Small.
The F&CC coaches also have larger windows - part of the reason for the longer length. There may be some other differences as well, but those are the main ones I can recall.
BTW, those F&CC coaches are virtually identical to coaches the C&S had, so can be used for that road as well. The C&S had no Jackson and Sharp cars.