Header Bolts and Head Torque specs

[6banger]

I blew a head gasket (Fel Pro 1007) that was mated between a stock block and a M&A Aluminum stage III head. The machine work was done to accept the "0" ring. My questions are: Is there any special way to torque down the heads? And what would the final spec be on this combination? I`ve built engines before but they had the bowtie on them. I`m familiar with the sequence of tightening the bolts at a said spec and then going around again, and how it varies with the lube and or sealant you use on the bolts. Since this is straying from a "Stock" assembly, I`m looking for input from past experiences.
The other question is has anyone found a good way to bolt up a ATR stainless header? I`ve got a mix of allen bolts and 6 point heads holding them together, some are tough to work with. Is there a 12 pt. bolt that may work?
Any input would be appreciated

Thanks,
Jim