Most of the bigger outboards from merc, are exactly the same motor with different ECU's(not sure about the opti's), For example a 225EFI, and a 250EFI are the same motor, if you want 2 225's, just trade your 250 ECU for a 225, if you want 2 250's, just get a 250 ECU and a 4 hole intake(some 225's already have the 4 hole).