If you're using the ute as a ute, ie carrying stuff, consider something like Kings HD springs for the rear - they sit at the same height as regular kings springs, at whatever height you choose, but have a higher spring rate, so they don't compress as easily. Can make it a bit of a pogo stick if you drive it empty all the time though.
Also keep in mind that the 100mm rule is technically meant to be considered when the car is at it's maximum (or at least a significant portion of it) load rate, although the likelihood of that being adhered to on the side of the road isn't great, unless you piss someone off. So passenger and 500-ish kg in the back. There is also a percentage of original suspension travel that you need to maintain - can't recall off the top of my head what percentage though - I'm thinking it's something like 2/3 but you should confirm that if it's a concern.
I'll let you know later when I'm home
