I know this is an old post but I would really appreciate any help you can give!
I am trying to install osx 10.11.3 on my 2570p using essentially the same method you have used (except that I am following the El Capitan tutorial
http://www.tonymacx86.com/el-capita...-hp-elitebook-probook-others-clover-uefi.html). I have made the installation USB flash drive and changed the BIOS settings, and I can load the installer, but when I reach the point (in the installer) where I am asked to select the disk on to which I want to install OS X, my primary hard drive doesn't show up. The only option is the other partition on the USB flash drive. I have tried multiple drives to no effect. I have also tried converting the drive to gpt using GParted. I am out of ideas and have been trying to figure it out for ages!
Does anyone have any suggestions? Thank you!