Pro laser head mount

[mixer911]

I purchased the pro laser head and need to mount it to the 1200x1800 gantry. The stock head has 4 screws that hold it on. The pro head only has 2 and they holes are bigger. Has are people mounting these heads? I used some washers for now to temp hold the head on, but it does not make it easy to align the head since the screws are smaller than the holes in the head mount.