LP2 brackets for what?

[Darrin Wright]

I have these 2 mounting points on the inside lower LH side of the rear hull, that I do not know what they are for.
This is an early Newport Railway hull that has been converted to a 3"mortar carrier. There are some later hull modifications (such as the ration box position on the LH side directly behind the air scoop).
I am not sure if these mounting points are in late war carriers or if they are a 3"mortar modification.
The pic shows the 2 mounting points chalked in white so you can see them.
Any help greatly appreciated.