Boy you can say THAT again!!!!! On the bolt thread angle of a LA intake: it's NOT 90*to the intake flange. They are 7* off of that.i found that out the hard way. .I took a set of magnum heads in to a regular (non automotive) machine shop with a set of LA intake gaskets and told them to drill them out, they did so exactly perpendicular to the intake surface and when I went to assemble it the bolts only touched on the outer(valve cover side) surface of the intake, there was lots of daylight under the bolt heads towards the inside of the intake. I ended up using those heads with their original threads as manufactured on another magnum engine.