Frozen water pump bolt

I'm going through freshening up my 70 340 and I'm getting ready to replace the timing chain, water pump, hoses, plugs and wires. Started disassembly tonight and the same water pump bolt that broke in my previous 340 is frozen in this one too. I haven't broken the head off the bolt but I am seeing it in my future. I took all the other water pump bolts out and I can get the pump to move and the bolt isn't so its frozen in the damn timing chain cover.....again...... I'm sure this is pretty common since I'm 2 for 2 with the same issue. Is there any tricks I can try. I'm soaking the hell out of it with PB Blaster now but where I'm spraying is nowhere near where the problem is I'm afraid. I've been pounding on the bolt as well. Should I take all the bolts holding the timing cover and starting pounding on it too? I can hit it with a torch but like I said before the problem is down deeper in the timing cover I think, I'm hoping someone here has a trick to get this issue resolved....Thanks