Macbook pro 15 inch 3.1 early 2008 Does not show Lion USB bootable flashdrive as option in startup manager (but does show up at startup disk). Goal: clean Lion os install on one primary partition. DVD drive does not read Lion DVD I burned. I do not have self powered external hard drive. So far the only way I was able to install OS X Lion was to partition hard drive into 2, 1 partition for Lion install, 2nd partion to restore the USB Install ESD to in Lion recovery disk utility which does show up as an option in startup manager once on hard disk. However, I want to boot directly from USB so I can wipe both partitions and have one hard disk partition and perform clean install. Things I have done to 8 gb USB: made guid partition table formatted USB mac os x extended journaled did restore of Lion Mac OS X Install ESD Note: rEIFt does show a bootable 4gb usb windows 7 option but not the 8gb lion install usb. Any suggestions?