Is it possible to vertically position a custom UIBarButtonItem?

Question

I have a custom UIBarButtonItem, consisting of a UIImage and a UILabel. Set up as such:

        addUsersButton = UIButton()

        barButtonView = UIView()

        addUsersImage = UIImageView(image: UIImage(named: "add-users")?.withRenderingMode(.alwaysOriginal))
        barButtonView.addSubview(addUsersImage)

        addUsersLabel = UILabel()
        addUsersLabel.text = "Your Table"
        addUsersLabel.font = ._8RobotoMedium
        addUsersLabel.textColor = .wayDarkGray
        addUsersLabel.textAlignment = .center
        barButtonView.addSubview(addUsersLabel)

        var space = UIBarButtonItem(barButtonSystemItem: .fixedSpace, target: nil, action: nil)

        var rightButtonItem = UIBarButtonItem(customView: barButtonView)
        rightButtonItem.width = 30
        navigationItem.rightBarButtonItem = rightButtonItem

With constraints like this:

        addUsersImage.snp.makeConstraints { make in
            make.top.centerX.equalToSuperview()
            make.height.equalTo(addUsersImageHeight)
            make.width.equalTo(addUsersImageWidth)
        }

        addUsersLabel.snp.makeConstraints { make in
            make.centerX.equalToSuperview()
            make.top.equalTo(addUsersImage.snp.bottom).offset(addUsersLabelHeightOffset)
        }

however the actual bar button is sunk about half way into the bottom of the navigation item, and bleeds into the view controller's main view.