wiring harness

[nicoaim]

I'm replacing my 70HP 3 cylinder 2 stroke Mercury to 850 HP 4 cylinder 2 stroke Mercury , Im wondering if possible to
use the 70 hp switch box and external harness wires on the 850HP engine harness?

 

[faztbullet]

With an adapter you can

 

[flyingscott]

I am curious how can you use a 3 cylinder switchbox on a 4 cylinder?