You should always use a torque wrench to tighten head bolts(first stage requires about 55 ft/lbs). Then, they are sequentially tightened thru two stages of 90 degree increases. That is, after initial torquing, repeat the sequence of 90 degrees for each bolt two times. DO NOT TIGHTEN THEM THRU 180 DEGREES ONCE. Do it in three stages as the book states. BTW, since you have already squashed your head gasket, with your previous eforts and since that was the presumed cause for your initial problem, I would seriously recommend not using that head gasket again. They are not designed for repeated use.
2000 Dodge Grand Caravan SE
No matter what you fix, there will always be something else to fix..
"Warranty" is just another way of postponing the inevitable.