I pulled my intake manifold today to get rid of an oil leak. When I put it back on, I had some problems tightening some of the bolts. The manifold was definitely aligned right when I put it back on, and the gaskets are all lined up correctly.

However, two of the bolts on the passenger's side will not take a preload. They are both past finger tight, but will simply keep spinning if I try to torque it down. One won't take more than about 5 lb-ft before it starts slipping, and the other will take considerably more, maybe 25-30 lb-ft (but still less than the 35 it's supposed to have). I'm guessing this is a sign of stripped threads, would replacing the bolts/studs in question solve the problem?

Right now the RTV is curing on the manifold, so I would like to leave it on if possible. Both bolts are toward the center of the manifold, so I considered just leaving them and seeing what would happen, though my better judgment says that will probably lead to a blown gasket. Any help would be appreciated.