Expect to have to do some grinding on both the Fentons and the intake where the clamps go. The Fentons generally do not match up very well. You'll want to test fit, see where you need to grind, take a bit off, then re-test fit. Another thing you'll want to consider is taking out the alignment dowels for the exhaust manifold at the front and rear of the head and replace them with studs. Thsi will get you 2 things, 1 is a more secure way of installing the Fentons, since they can't be assembled to manufold in a unit like the oem exhaust. The other benefit is better clamping of the manifold.
I didn't have any problems removing the bolts on mine.
