So long story short.. awhile back when I was putting my turbo on and tightening the nuts for the exhaust mani, I cranked the very front one a little too much and stripped it out from inside the head. I said F-it and kep procrastinating and never did it. This week im putting on my new S15 T28 and I want to fix it before I put it on. But I don't know what size to drill it out to and which helicoil to use. Can anyone help me out?