I want to move a fuel vent, and it's in a spot where I think a truss head machine screw would look just fine. Problem is the hole is a bit close to the head-diameter of the largest truss-head screw at my usual source (mcmaster-carr). (It's above the water line and only leads to the cockpit, so structural strength is not a problem, and even a leak would not be catastrophic.)

The largest size they have is 3/8", which has a head diameter of .82
I think the fuel vent hole is going to be something between 3/4" and 7/8" (it's a 5/8" vent line), although I haven't removed the vent yet because I was hoping to have my "repair" in hand first; if I can't get a truss head screw (or something else with a flattish head that I don't know about?), then I may go to a different solution. I guess it may just be too large a hole for this solution, but figured I'd ask while it was a current topic.

Thanks,
CCA-Boater