Hi Luke
I cant tell you the spacing off the top of my head but the sizes are usually 14mm for NATO holes, 16mm for standard towbar, or 10mm for the big bracket Ralph was on about, usually 2 16mm holes at the bottom centre, 4 14mm nato holes above that spaced around the centre of the x member, and either 2or 4 10mm holes depending on which dixon bate you have...
Clear as mud?
You are welcome to pop over and measure the 110 or the 109 up, both have nato hitches and I have a drop plate thing too that you could measure,
Mike