I had HUGE difficulty lapping rails with Carbon, it's so stiff that it wants to straighten back out. If you want to lap by hand using epoxy, watch it carefully or use some X-55 accelerant to kick the epoxy quicker.
I also found that Carbon frays something miserable - cut laps are the best, or paint over the laps to hide the mess.
Finally, in my experience when Carbon fails, it produces shards that puncture skin like needles. I would cover the carbon with a layer of 2oz...will still allow that look without the potential bloodletting