This production launch has been the highlight of my short engineering career. Regardless of the outcome, even if it's a total flop, I have learned so much. How much clearance do we need? What dimensions are important? Why can't we just have one option instead of four? Tolerance stack up. The list of lessons is long. For this health degrading, stressful, tiring, train wreck of an experience (bit of an exaggeration) I am thankful.
My advice to future engineers: be part of a production launch as soon as you can, and further more, understand the product you work on.