I think your M106 lines would stay the same (or change very little). You will need to add a M950 line to define each fan. So in my case, this line defines fan #0 (F0) as the "fan0" header on the Duet (but you are free to define fan #0 as any fan header you like). Then M106 can reference fan #0 by specifying P0. Code: M950 F0 C"fan0"