Oldtown PDL nut.  I printed in ASA.  The 3/8"-24 are difficult to get correct without cleaning them up.  I decided to chase the threads with a tap to ensure a good fit, but I added 2 clearance tolerances options for those that have a well-tuned printer.  

No supports needed.  I printed on the High Temp Plate with Elmers Purple Glue Stick.  No brim or supports needed.  I did not preheat the chamber or add a brim.