I've seen quite a few 41-46 trucks in my days, and only seen one style grill for those years, either chrome or painted.
The trim pieces at the top of the lower grill were stainless for the chrome grills and painted steel for the painted grills in my experience. There are twist "tee" connectors that hold that trim in place similar to the connectors for the hood side trim on the 41-46. They are easily removed if you have access to the back of the grill. If you try to remove the trim without untwisting the tee connectors you will likely damage the trim.
The after market grills for the 41-46 trucks have that trim spot welded to the upper portion of the lower grill. The after market grills can also be easily identified by the bottom of the lower grill, which is also spot welded on, as opposed to the original one piece stamped grill.
