Hello all, I hope I’m in the right area. I’m just repairing a pressure regulator of a preheater. I bent the edges, cut the seal and want to get the whole thing back tight. However, I don’t know how best to do it when drilling the holes. I have drill bits in 1, 1.5 and 2mm diameter. Dimensions of the screws I imagined 1.7 mm, but also have others there. Material is the top I think brass is the other steel or uh In between a 0.5mm thick rubber seal. How big should I pre-drill the holes so that the screws hold tight in it? Attached is another picture as it should look. I would leave the edges on it. Could it work away if necessary. My variant would be to pre-drill the holes in brass + steel with 1.5mm and screw them with 1.7mm. Or rather 1.5mm in brass and 2mm in steel? Thank you very much!