Here's another idea on this subject...I don't know how hot the propane torch makes the bolts..but, why couldn't you just "bake" them in a 400* oven for a half hour or so and then do the oil bath....if opening up the pores in the metal is the goal then this should work....you could also do a bunch at one time....just an idea.
ps...don't use your wife's good roasting pan
