Swapping engines in a Mark Twain boat

[sa43]

I have a new Inline 6 Mercruiser engine that I was going to put in my 1978 Mark Twain V Sonic but I found a 1990 Mark Twain 200 with a OMC Cobra 5.0 engine with a busted block. Will my inline 6 have enough power for this boat?

 

[Bt Doctur]

I doubt 160 Hp would move that boat very well