From what I have seen, the install would definitely be easier before the fuselage is all closed up (wiring, tunnels, etc.). Also, there are a number of mods required inside the engine compartment.
RV-14A Builder - kit #136
N314KC - First flight Mar 8, 2017, >300 hrs
Sport Pilot (weight-shift control) - Airborne XT912
Dues paid 11/2017