The instructions I have for a 2006 284 with two stage clutch is that the fully released pedal should have a 2.5 to 3.0 mm clearance between the throw-out bearing and the clutch fingers. This should give you 3.5 to 5.0mm of "free" travel at the end of the rocker arm where the clutch push rod attaches.
What kind of clutch issues are you having?
What year tractor?
Dual or single stage clutch?
I can't answer the question about 3 finger and 6 finger interchangeability, but my instinct is to say no. Without knowing all the specs for each clutch it would just be a guess. Things like, bolt pattern, dual or single, Height of clutch pack assy. Diameter of disc and plates. Size and spline count of the transmission input shaft and several other things.