If it was blowing steam, the die is cast.
Time for a new HG along w/checking the calibration of the torque wrench you used to torque the bolts.
Use a torque wrench to remove the bolts in reverse order. If the break loose torque is excessive (indicating the bolts have been over torqued) OR is insufficient (indicating the bolts have been over stretched), OR if there's any question in your mind that something might have been done wrong that could have damaged the fasteners, I'd want to use fresh hardware. If they were over torqued and were right at the edge of deformation, heating the engine up could have been enough to break a bolt outright. Assuming that, the rest might not have been far behind, and could have become over stretched.
Note- be aware that the break loose torque is less than the applied torque in most cases. If some sort of sealer that sets up and/or hardens was applied to the threads, the break loose torque may be higher than normal. Even so, look for uniformity
between the bolts as you loosen them. If you find any that are quite a bit easier to loosen you know you've got a problem, and I'd recommend replacing them all.