NM51,

I would call this "my kind of luck". It seems that It will have to be removed for repair...that's obvious. Would it be possible to take it to a automotive machine shop that pressure tests aluminum heads, and have them locate and weld the leak.

There is a shop down the road from me that does a lot of Toyota and Volvo engines. They have a tank and various blanking plates to test the aluminum heads for cracks for a "go/no-go" determination.

I believe they have TIG capabilities to deal with repairable cracks.

It actually might be cheaper to invest in a new manifold..sometimes you have to bite the bullet.

Stuart