Rendering of diaphragm cover, modeled in Freecad. will be attempting to print in TPU, but I have concerns about supports... will update as it progresses.
Edit#1 Support worked out surprisingly well. Thickness of outer ring was too much to assemble the reg, and the overall stiffness was a bit much. Will try the v2 when time permits.
Edit#2 v2 reported as useable, but a little stiff, with 95 duro TPU. v1 files removed
Edit#3 v3 added, slightly thinner in the domed portion than v2 but sealing surfaces remain the same. My test print works well, comparable to stock purge cover. Leaving v2 files up if anyone wants a stiffer purge.