Finally pulled the trigger

on my first muzzleloader for hunting. After weeks of researching I bought a Knight Long Range Hunter - western ignition, thumbhole stock, .52 cal. But here's my trouble - finding the right rear peep sight for this rifle. I had been set on the Williams FP Legend but after buying the rifle I ran across the internet threads showing how it wasn't working with the new LRH - they were having to grind some width off of their bolts to pass the right side of the sight mount

I called Williams today and talked to Steve - he said they just recently realized the same issue with the new LRH and Disc rifles using the FP legends. He said they're looking for a loaner rifle to work up a new mount but it wouldn't be ready for awhile.
So I'm considering using the FP legend but mounting it in front of the breach - I have no idea if this would work well being further from my eye - your experience would help me on this idea.
The other choice is to find another peep solution that's known to work for these new rifles. My preference is an FP type peep that isn't surrounded completely by additional metal but having looked at a ton of sights I really need some feedback -
Thanks in advance for helping out.