Pin Hole In my J Head

Hi there i was just wondering if many have come across this problem. I have a set of J cast 360 heads with a pin prick size hole in the intake short turn, i am a bit worried about putting these heads on as the hole is on top of the coolant gallery.
I have been told to put some sort of chem weld in the cooling system on first start up as it will help seal, evidently the area is to thin to weld. i need these heads to get me around on the street and for a little bit of drag race use. Would i be silly to put these on and give them a try? cheers Daniel