RE: carbs, props, and plugs
Contact FPE and see what make and sized prop they use.
As a side note I have a Sachs based 3.2 engine with a J&A Peacekeep inverted pitts muffler. I fly at 5400ft. My engine turns a Zinger Pro 22x8 @7500 rpm. The pro may not be everybodies(anybodies) favorite prop but its what I can get. I'm going to look at some 23x8 later..