I'd tell you that I have never broken a manifold bolt off in a head, but I don't want to jinx you.
Cheap solution, it works most of the time. First, be sure you have the intake rings, they slide into the head and manifold and help keep things aligned. Also a new set of gaskets and a tube of ultra-copper rtv. Remove the manifold set and clean the mating surfaces. I then put a bead of rtv on the mating surfaces of the manifold and install with the new gaskets. The rings can be stubborn, so have a little patience. If you need to, you can put some rtv on them to hold them in place. Tighten down the manifold bolts, but do not over tighten. I don't recall the torque specs, but they are low, and you can't get a torque wrench on most of the bolts. If you have pins in the end holes, they can be removed with vise grips and replaced with bolts. After tightening, inspect to be sure rtv has oozed out all the way around the ports. Then let then engine sit for a day allowing the rtv to cure. You can then trim off the excess with a razor or knife, and run the engine. In most cases this will solve your leak problem.
