Yes you will need a separate boot lun for each host, and that lun will NOT be exported to a hostset, or a member of a volumeset. For simplicity, I would recommend using LUN0 for the boot drives. One unique VV exported as LUN0 to each esxi host.
As for the boot options, that is done on the server BIOS configuration. You need to make the HBA higher in the boot order than NIC, SATA or other scsi cards, and go into the boot bios of the HBA and set which LUN to boot from.
The gold standard for all things 3PAR and Vmware is the
3PAR Implementation Guide for VMware. Page 103 is where SAN boot is discussed.