Yamaha 3.0 Head Design - unique??

[CDNSPORTSTER]

Does anyone know if Yamaha designed / manufactured their own head for use on the GM 3.0 block?
I think I have a leak from the exhaust gasket, and hoping I can use a gasket from a Mercruiser or similar.
Advice...?
Thanks in advance,

 

[Scott Danforth]

Yamaha bought complete longblock and added their manifold and accessories. the Head down to the oil pan is all GM.

 

[CDNSPORTSTER]

Understood,
So that is good news as far as just needing a Gasket vs a new Manifold.
Thanks Scott!

 

[Scott Danforth]

What makes you think it needs a gasket?