My rule of thumb on deep ripping: Get the biggest dozer you can find with the deepest ripper and pull it on contour when the soil is at it's driest. This causes the pan to shatter. Plant into the rips in the second winter when the soil has consolidated. You can plant first year if you are prepared to go in with hand tools and prepare each planting space or have plenty of seedlings to spare.
I would question the use of eucs if you can avoid them. They are just too invasive and rob the soil, etc. I'm sure I said it on an earlier post.
Jeff Nugent, SW W.Australia 34deg.S
Mediterranean climate -
Hot, dry summers. Cold wet winters. Rarely a frost.
200m elevation, 75km from west and 60km from south coasts.