I need to install a stainless steel 2 gang blank plate on a 4" box mounted in a concrete block wall. The project manager doesn't like the look of the regular 4" blank plate. I tried to us a mud ring turned to the inside, but the screw flanges inside the 4" box are in the way. I can cut them off with a jigsaw, but wondered if anyone else had a better idea. Maybe one of those data plates????

They do make flat plaster rings.

They make a 2 gang flat plate then install a stainless 2 gang blank plate.

Flat Plate part number is "Iberville" 52-C-00
the stainless plate you want has the holes that line up to the device mounting screw holes not the plate screw hole mounting. (Box Mounted plate)

Part number would be such as Pass & Seymour S23

Thanks, I'll call my supplier Monday.