Repower from 351 Ford to 350 GM

[Captain Crispy]

Anyone here have any real world experience replacing twin 233 hp Merc 351 Fords with 350 GM in a 1970's Weekender ?
What I am concerned about, obviously, is cost. Do I have to do any structural changes to stringers, bulkheads, etc. to mount the engines ? Would it require a different transmission ?
What I am getting at is whether I would have to do anything other than replacing the engines, manifolds, and risers ?

 

[northern]

Based on what I have been told about repowering it is best to stay with what you have as it should mount the same. Have you concidered having your engines and transmissions rebuilt? A friend paid 10,000 plus engines to repower to different engines and generator. There was modifications to supports.

 

[Captain Crispy]

I haven't actually gotten the boat yet. I am eyeing several '70's Weekenders, including SloppyJoe's, but can't pull the trigger until some things finish up on the home front.
My concern about the Fords is the availability of parts, including a freshwater cooling kit, if I put new short block Fords in when the existing motors crap out.
Found the freshwater kits at ebasicpower, so i am sure other sources are out there.

 

[northern]

I had a 28 footer with OMC 3.8 stern drives. Parts kept getting harder to get. It got to the point it was time to sell or put new Mecruisers in. I sold and took the loose of all the upgrades done. An old used boat is just the next owners problem.
Good luck