To add to Danny's answer.
If the manifold bolts are broken you can get a template that allows for them to be drilled out if they are broken even with the cylinder head as often happens. If you have access to a torch and welder you can sometimes weld a nut on the broken piece and heat it up to remove it. If you have the typical cracked manifolds there are a couple aftermarket ones that last a bit longer, but they are more money.
A couple videos on them.
Sunday, March 28th, 2021 AT 3:06 PM