Time To Take Stock.....
After a week hiatus I revived with new inspirations on how to proceed. The Lower sixth of the cannon assembly vexed me until I realized where my problem lay. It is pretty much what is found wrong with a majority of scratchbuilds; they are too square and straight sided. The lower rail needed some slight curvature to the sides and base.
Fortunately the material I am using has a taper for ease of extraction from the mould.
Playing on that feature I came up with the correct angles to duplicate the artist's rendering.
This will be more apparent in subsequent images.
"It is easier to deceive people than it is to convince them that they have been deceived."