I would always 'chase' the threads after a project like this. Avoids surprises on reassembly. Even tho I plan on running aluminum screws in EVERY threaded boss in the case during anodizing to prevent losing my chassis ground due to non-conductive properties of anodizing. But I'll have to take lots of documentary evidence with me concerning those screw specifications as they'll be highly suspicious when they see those screws. As I mentioned earlier one steel screw could contaminate the whole tank and compromise ALL other parts in that tank being anodized besides mine. Depending on tank capacity and other parts in with mine that could cost them a few hundred to tens of thousands of dollars and I can't fault them for being careful. 6 ruined Aerospace parts from Boeing or Lockheed Martin in the tank with mine simultaneously could seriously ruin several people's day! And its still possible they could deny me the use of screws just out of overly-cautious concern.. If so then I'll have to invest in a solid carbide M3X.5mm bottoming tap to chase all the threads as due to hardness a regular HSS tap won't cut it post-anodizing. But a chassis ground cannot be compromised! This is unchartered territory for me with the screws tho hopefully with documentation, a magnet and an explanation as to "why" I need to maintain a chassis ground via those threaded bosses they'll understand.
Statements in my posts are opinion only, not to be construed as fact. Any projects I engage in are at my own risk! Their outcome cannot be assured and may result in success, small/no change or catastrophic failure. I encourage no one rely on anything I say or do as gospel and to realize your mileage may vary!
