The biggest problem will be getting the weight out of it. I have been removing a bunch of stuff from my FF to try and get it close to min weight with a full size pack.
You need to move everything as far forward as possible. I have found that to make my FF drive better.
You should have no issues getting the FDR you need. I can get down to a 3.16 with no modifications. You should be able to change the spur, maybe the upper pulley, and get there no problems.