Jeff --
I recommend one not use bolts to secure the head/cylinder to the case.
Use studs instead.
As to where to source and the part number -- Read this post .. I don't know who he is -- Butt looks like he did a damn fine job ............
http://www.rzrforums.net/forced-induction/33077-big-bore-head-bolts-high-boost-applications.html
To answer the question at the end of the story - Yes .. One does have to machine off the Bull Nose. Chopsaw or hand grinder also works.
:ride: