I just wrapped up a project that required a lot of custom machined parts, kind of nice when all the parts come together. Kind of funny I made another part that looks like a crack pipe.
It's a float bowl adjustment too. The fuel gets into the clear tube that has marks to show the tolerance for the float adjustment. This required a deep hole bored all the way to the end where the tube goes. It has cross drilled holes to allow it to flow. There's a sleeve that seals the apparatus. The tube itself was constructed from a more exotic plastic that had to be annealed, chemically treated and re annealed. I bit more of a project than I planned, but it was fun.