A side note that might rain on some parades to some extension but deserves to be mentioned. For what I can see Dynamo kit features the long-nose turret shield originally designed for the M16 half tracks though the box art shows the shorter snub-nose.
The Quad .50 had two different designs of gun shield assemblies, a shorter on the M45C mount, and a slightly longer on the M45D/F mount. Difference was that the shorter M45C was designed for the trailers and M45D/F was made for the M16 half-tracks (and navy IRC) that had higher mounts for a lower depression (as these were mounted on elevated positions).
I don’t know the mix of these during WWII but “post M16” both M45C and D/F ended up on the gun trucks in Vietnam (and later liberally applied on all types of mounts as of collectors). If you have Doyles Gun truck books there is a good shot on p.49 in the old one and p.60 in the new Squadron signal of both types on Quad-trucks in the same shot.
The M45C is still predominantly seen on the trailers, though people can probably dig up some pic the D/F in ground position trailer as I assume both was used on trailers as the M16 was retired. As seen on gun trucks in Vietnam an additional base ring was sometimes added to the trailer bed to give better height. Both M45C and D/F used single and double ring outfits on Gun trucks in Vietnam.
Pic left. Snub-nose [a nickname of mine, ie. unofficial] standard, single base ring. Pic right. Long-nose on a double base ring on Gun truck (this is not an original vehicle but a museum one, but montage is identical to the ones used in Nam). Note how M45C ends above the bolted turret ring and its blunt nose, and how the longer nose M45D/F “M16” with its sharper end is covering it.