PS2 PAL v4R BOARDS

Is anyone aware of the differences between v4 and v4R boards? The latter is a 30003R which is not a v5 (by reference to the v5 photos) and isn't an classic v4 either, differences being around the area where you would attach de-green or macrovision defeat points.

Observations welcome.

This is in relation to our unsuccessful attempt to install the Elvis Messiah Clone on a 4v4R board.