Cracked 906

So I have been chasing a coolant leak for the past few months and finally located it. I thought it was coming from the header bolts initially. We decided to take the header off to further investigate the leak, which by the way the 2" tti headers are a real ***** to get out! Especially the drivers side, the one that needed to come out. After removing the header it was obvious we had an issue. We found a hairline crack just below the exhaust ports on cylinders 3 and 5. The crack is about 2 inches long and hard to even see but big enough that when you would rev the engine coolant would spray out of it. Is this a common problem with these heads or am I just a lucky guy? A lot of work has gone into these heads and to duplicate one would be costly and time consuming which neither one is good at this point. I need to get it welded up and I have a line in a guy who is great with cast iron welding so he will get a call tomorrow. Pinks all out is saturday and I will be there, come hell or high water! Here is a picture of the affected area.