Since my last post I broke apart the gun cradle because the pivot side plate wasn't right. On the left was the part that was already glued in place, in the middle was the part I thought was correct and on the right is the final corrected part.
Here you can see the cradle in pieces.
And hopefully this pic explains my reasoning. On the middle part I could have glued two fillets into the open areas but in the end I wouldn't have been happy with it.