OMC has two types of throttle/shift cables. Type 400 is pre-1979, Type 479 is 1979-up. As far as I know you would not be able to adapt a pre-1979 cable from your existing box to the newer motor nor could you adapt a 1979-up cable from the newer motor to your old box. Pretty sure you would need a 1979 or newer control box to make the swap. The plugs where the control harness connects to the engine harness have to be the same color, red to red or black to black. I can't comment on the motor mounting as I don't know when they standardized the bolt hole spacing. But you could always fill the old holes and drill new ones. I just saw your original post that was answered by SwarmyWench about the bolt holes, I thought they would line up but wasn't 100% percent and didn't wanna speculate.
