[Michael R.]

The image of the crew washing the carrier shows a MK-I mortar carrier, the gunner side bracket on the divisional wall upper angle iron is one of two for mounting a rifle. A Forum search shows a few images posted by others over the past few years.

I believe you will find your carrier has been modified or updated to the standard MK-I* choke control cable routing installed to suit your Zenith carb. The cable conduit has the correct mounting bracket on the driver side engine head. If you follow the conduit back through the divisional wall you see it running along the right lower hull side, without the later retaining plate installed to keep the conduit against the hull wall. The issue here requiring the later retaining plate was the fact the choke control cable conduit does not travel under the cable cover at the driver right side track guard.