Thanks to everyone for your responses - this is an amazing group. I have followed the threads mentioned above, as well as the huge number of conversations on this subject. This coach is new to me so I can't comment on the noise - the crack is obvious and I can literally feel the escaping gases.
Sounds like best path forward is to bite the bullet and get the new manifold set. This will give me a chance to get acquainted with the turbo, replace its oil lines etc. etc. Like I keep telling my wife - this coach is not just an investment, it's a hobby. And it's cheaper than golf.
Safe travels and thanks again.
