I started with an 1/8" drill bit
, what happened was I that instead of hitting the center I driilled to the side of the vain and never saw it with the little bit. This was my first time and I thought I hit the right place, but when I drilled it out again with the 7/16" bit I found the vain I was looking for and it was to late. I would have to look again but I don't think there is enough room to put in a plug, do you think JB Weld or epoxy would work? I have heard that the pressure gets up to 900psi. with the restrictor drilled out. I know where there is two more boxes I can get cheap, maybe free. But I do hate messing that one up, I would be done by now.