Yes, that’s what I mean. You’ll need to get the Kroil (which is great stuff) on the inside part of the bolt threads and that’s the only way that I can think of. Applying a lot of force to the bolt heads will do one of three things and two are bad. At best the bolt will break loose and unthread. More likely the bolt head will snap off. The worst case would be for part of the block casting to break out around the bolt. This is NOT something to be rushed. Bolts are cheap but blocks are not.