Context Menu positions

I've got a UserControl which is used to show our own Popup menu's within certain screens via either right-click or if placed underneath a button, will show one there. It use to work via a standard inbuilt VB6 Popup Menu as CJ Skinned this nicely and it pops up based on the position within the UserControl top left corner.

We recently found an issue with the SkinFramework which skinned the menu nicely, but if the popup menu had a large number of items, the scrolling feature of the menu is lost!

I thought of a quick work around (which introduced nicer skinning too) which was to use the CommandBars Context Menus and use a popup from there. The issue I now have though, is the X and Y co-ordinates of ShowPopup method actually are for the position on the screen, rather than within the UserControl's top left corner like the default VB6 one. This is causing me a real pain when trying to show the popup in the correct position.

Just in case I'm asked why am I still using this UserControl... simply because due to the vast amount of places it's used and projects it's shared, it's best to keep it here.

So... my question is, is there any way I can find the UserControl's position on the screen, or perhaps even get the scrolling working on the old VB6 Menu control when it's skinned?