i cant speak for MMThor, but im a OEM freak; anything i change or add, if it came on another model, must be mounted in the same location, using the same wire colors, and using all OEM parts.
for example, im adding power door locks and power windows on my project Honda civic hatch. that year (1995) none of the hatches had those options but the coupes did. so i swapped in the wire harness, window motors and locks form a coupe that had them. so in the end i have a unique car with OEM options that were not on that trim or type of car. same with the RV